When I first started my career in racing I knew what I wanted to do. I had always wanted to be the guy who setup the car. You might relate. Sure, driving would be cool, but how many of us have the talent to do that and do it well. And now days, you might need to be the son of the team owner or related to the sponsor or whatever to fund that.

The next coveted position on the team is the setup guy. You can call him the crew chief (this is usually the case), the engineer, or the car chief, but whatever the title, what this person does is envied by all.

As I moved around the county on the Tour, for each team I ran into, there was always one guy who was in charge of the setup. In my consulting days, when I arrived at the shop of a new client, there was the setup guy and we either got along or he didn’t want me there to critique his methods, the later being the norm. Behind him were several want-to-be’s who wished they were the setup guy.

I have to Note here that I have never seen a Setup Gal in all my years in racing, but that doesn’t mean there isn’t one or that there won’t be one, just that I’ve never seen one. So I will refer to “guy” here to mean all setup persons. There.

The setup guy is the one that can make or break the team. His decisions are what constitute a good or bad car, race, and/or season. It really isn’t the cars fault though if things go wrong. And everyone around that guy seems to have an opinion. These are the want-to-be’s and I don’t say that with any disdain. There can be a use for the other potential setup guys in the shop.

My opinion is that everyone on the team is important and has a desire to help the team win. What should happen on every team is that everyone should be allowed to be heard when it comes to setup ideas. Then, only that one designated setup guy person will make the ultimate call on setup. But the ideas presented can and should definitely influence the decisions.

I have consulted with some very high level teams, including Cup teams in the past. I never push ideas on the crew chief. I listen and discuss items when asked. But, when I hear or see something I think might help, I speak up. The crew chief knows I don’t want to interfere in his setup process, and when I do speak out, it must be important to me and he listens. It is a mutual respect relationship.

The ultimate goal of the up and coming setup guy is to one day be the setup guy for this team or another. To get there, you need to learn all you can about the car, the setups, the maintenance, etc. because when that day comes, you’ll be all alone with a ton of responsibility on your shoulders.

So, my advice to all of you setup guy want-to-be’s is keep on digging and working to help the setup guy. Respect that he has a lot of weight on his shoulders. After all, he is going to either be a hero or a zero at the end of the night. It’s a tough position to be in and it takes guts to do that job. Learn all you can from him. If your learning exceeds the crew chief, don’t get pushy, you’ll get your chance.

Develop a relationship whereby he knows you respect him and his knowledge while at the same time letting him know your desire and need to participate on some level. If you can do that, he will appreciate your understanding and will let you into the process at some point in time. Then it just might develop into a setup team.

If you do get to be the setup guy, don’t forget how you got there and that there are some around you who desire to be a part of the process. If you let them participate, they can be a real important and needed asset to you and the team.

If you have comments or questions about this or anything racing related, send them to my email address: chassisrd@aol.comor mail can be sent to Circle Track, Senior Tech Editor, 1821 E Dyer Rd, Suite 150, Santa Ana, CA 92705.

Tire Soak Question

Bob,

I’ve read your book, have your programs and have being using them at least twelve years.

I was reading your article on tire soaking. I’m a road racer, so I don’t know much about soaking tires. But I did buy some tire prep (Goat Pee) about a year ago. I put it on my tires that had a qualifying and a 30-minute race on them and went to a track that is hard on tires.

They corded very quickly. I put the same stuff on before an event last weekend and just put it on the center 6 inches of a 10 inch tire. The track I went to was not hard on tires, and it seemed to make the tires better for several 10-minute practice sessions. I can’t make my car handle well on Hoosier tires.

I’ve been running on Goodyear 2902s for about three years. Since Goodyear have not made these for several years now, all the 2902s I can buy now have been sitting for quite some time. Is there any particular tire prep that you have come across that you think would help these tires? Thanks.

(Name Withheld)

From what I have seen, you have to regulate the amount of treatment you apply. If you treat too much, the tire will be too soft and like you said, cord too quickly. It will take some experimentation to get it right, but start off on the short side of the amount of time you soak the tire.

To be successful, you will need to use a rotisserie to rotate the tire through the solution so that the distribution is uniform. You can time how long the tire is turning in the solution to achieve the desired softening.

What you are doing, bringing old tires back to new softness, is what I consider a legal and appropriate use of tire softeners. As long as you don’t exceed the softness of a new tire, or read lower on the durometer, you should be legal. That doesn’t mean the tech officials will see it that way.

The argument could be that the commercial tire softeners could make the tire wear better and make the grip last longer than the chemicals used in the production tire. That would be hard to prove, but it could be a valid argument.

For a circle track racer using the same tire, as a test you could run a new set of tires on a ten lap run, then an “older” new set that is treated to the same durometer reading for twenty laps and see what the lap times look like.

If there is no difference, then the officials have no valid reason to oppose the use of treatment. The other argument that you won’t hear outright from the officials or track management is that the sale of new tires makes money for the track. If everyone used treatment and their tires lasted twice as long, the sales would be cut in half.

About the Rules

Dear Circle Track,

I wanted to respond to a article in the CT Face Book page about rules. I have been run off from Five Flags in ‘05 one trip, Lanier Speedway ’04 – ‘08 one trip they are closed now), South Ga. Motorsports Park in ‘05 one trip (closed now), Greenville Pickens in ‘15 two trips with two different cars and asked not to return. So they’ll go broke before I go back.

But I have gotten pretty used to this at the tracks, it seems just part of being a Mopar oval track racer. I have fought tooth and nail for well over ten years to get changes to the rulebooks, similar to GARS and the Mid Atlantic Street Stocks, but most of these track have just lost someone who really loved the sport.

When a track burns me like I have been done they don’t have to worry about me ever coming back or any of my family or friends. Hard work should be rewarded. I have run my own company for 21 years. Like I tell folks, I’m a leader not a damn follower which 99.9% of people are just followers and have no clue to anything in life period and no respect for somebody’s hard work.

Ok what’s the point of this email? You are correct in what you have said. GARS & MASS is a good starting point for a great rules package that needs to spread across the country for a Base stock car class. Then maybe I could race my Dodge somewhere without being run off all the time.

Thanks,
Jody Cash.

Jody,

That was the intent of the GARS series, to develop an all encompassing set of rules that would include street stock class cars from different tracks and series. What it has developed into is maybe a formula for all tracks to use so that they don’t exclude anyone, like you have been excluded.

It is our hope that these exclusion tracks will see what we are doing and see that they are turning away back gate revenue while also reducing the field of cars. Fans don’t appreciate paying to see six or eight cars compete.

I invite all track officials to go online to CircleTrack.com and view our series website where you can view the rules package we developed. See how we compensate for different engine packages and chassis modifications. This plan is working very well for the races we have run so far.

Many Comments

Bob Bolles,

I have to comment about the old dogs write up. The best thing that could have ever happened to sprint cars is for technology to be left behind (exception is safety stuff ). Sammy Swindell had a rack & pinion dual a-arm sprint car back in the 90’s, and there has been many innovators try all kinds of different suspensions over the years. Thank goodness none of them worked any better than the old standard deal and never caught on or sprint car racing would be dead as we know it.

Dirt late models have run themselves out of business for the local racer due to the high costs of keeping up with suspension and engine technology. Sprint cars are for the most part the same as they have been for 20 maybe 30 years allowing local racers the chance to compete for a modest budget. The increased speeds over the years of the sprinters have mostly come from bigger and better tires and making the package lighter.

The tire on a sprinter is responsible for a great deal of the suspension characteristics, and with better tires comes bigger HP. On any given night you will still see a fairly big crowd of sprint cars at local Hoosier race tracks, where late models have all dwindled away.

The local late model driver has been forced to step back to a mod and race for $500 to win. It is my opinion, due to the unrestricted technology (modern 4 bar suspensions) the dirt mod is in compromise of dying out too.

Car counts are less than half from 10 years ago, just ask any promoter. If you hook a race car up better you can put more HP at it and lap times drop. It seems like common sense doesn’t it. Bigger and better engines costs big money. And it’s money the local guy just doesn’t have.

We are building 740HP Dirt Mod engines for customers and they’re hooking them up. That’s insane! If you want to grow a class at a local track the formula is easy, take forward bite away from the competitors.

Engine rules don’t work! No tech guy is going to tear down an engine at midnight after the races to inspect. Crates don’t work, they get cheated up and again no tech guy will spend the time to inspect. Simply limit the forward bite of the race car and the engine costs will regulate themselves. So what if the car is a second slower on the track, the fans won’t complain because the side by side racing will be better.

My proof is the truck race at Eldora. They have truck arm suspensions, and they were turning lap times comparable to the local Eldora street stocks and they still put on a whale of a show. Truck arms have no forward bite is my point.

I’ll bet the guys that ran up front used restrictor plates to take power out of their engines to help hook them up. It is my belief that local racing can be saved and made to thrive again if we would simply back off of some that modern technology we have been talking about. Thanks for listing to my rants.

Roger Williams.

Roger,

If we took away all of the modern technology, what the heck would I do? I’d have to find another job. Kidding aside, I do see your point, but in order to have racing, we need to keep the racers interested in racing. You might be mistaking the reason why the numbers of race teams has fallen. The economic downturn over the past seven years could be a factor.

I do also agree with your assertion that using tires with less grip would equalize the field, to a point. I’ve seen a crate late model dirt car win over a couple of high tech, very high dollar and horsepower engine cars. And they were all on very grippy tires. He must have been using some of that high tech chassis stuff with a low tech motor.

As to the assertion that tech officials don’t want to tear down an engine at midnight, I have these two things to say. It’s the tracks fault that the races are over so late. These programs can and do end much sooner if the promoter will move things along faster.

And, the tech guys are to blame for not enforcing the rules and looking into the motors, not technology. That could be fixed with the proper staffing. I have always said that sealing the crate motors was the wrong thing to do. Leave them unsealed and encourage the tech officials to have the guts to challenge the teams and inspect the motors.

As to the dirt modified class, the disparity in performance is not only with the horsepower difference, but in experience. Most of the back 60 to 80% of the cars in any mod race don’t drive very well and need lap time experience. Driving is a big part of success in dirt mods and that is a draw for both the racer and the fans.

If you noticed too, driving is a big part of the success for sprint car teams. Again, like the dirt mods, two thirds of the field just don’t drive as well, or as fast, as the front runners. In time they might, or they might never. It is a part of that type of racing. Technology will not make a slow driver fast no matter how much money they throw at it.

The post Stepping Up for Your Race Team appeared first on Hot Rod Network.

As our season goes along, we are prone to make changes to our chassis in order to gain performance. Sometimes these changes will affect other aspects of our chassis. It is important to know, when making a change, what other parameters are affected by that particular change.

In the GRIP seminar this year, Gary Crooks said that when he made a right rear spring rate change, he also changed the right side panhard bar height. The reason was this. If the spring rate he was changing to was stiffer, then the right side panhard bar mount would travel less and would end up higher than before the spring change. He would lower the bar mount by the amount the chassis travel was affected.

So, a change in the bar mount on that side was necessary so that he didn’t change two things at once, i.e. the spring rate and the rear roll center height. This demonstration of thinking out what other changes result from a chassis change is profound and something you need to learn too.

The following is a list of common changes you might make to your car that will affect other aspects of chassis setup. When going through this list, think back to changes you have made to your car and if you have not considered the other affects those changes made, then now is a good time to go back and correct what was affected.

Anti and Pro Dive – As you make changes to your anti-dive and/or pro-dive, you are also changing the arc of the tie rod ends. As the corner travels, using anti-dive, the upper ball joint travels rearward. When this happens, the spindle is rotating and with it, the end of the steering arm with the tie rod end is moving up.

We know that the tie rod angle affects the bump steer on our car. So, if we initiate a change in the motion of the tie rod end, then our bumps steer will necessarily be different. We need to check the bump steer in the range of motion it will be operating in. And if you change your anti’s, recheck and adjust your bump steer for minimal effect. Once you have re-adjusted your bumps steer, be sure to re-set your toe.

Caster Changes – Similar to the Anti’s changes, when we change our caster split, we move one or both upper ball joints in a direction to the front or rear. This rotates the spindle and like the Anti’s explanation above, moves the ends of the tie rod.

Again, this changes the angle of the tie rod and changes your bump steer. So, whenever you make a change to caster, such as introducing negative caster into the left front because that might be the trend, you must also recheck your bump steer at that wheel and correct it because it will be different than before the change. As stated above too, re-check and re-adjust your toe.

Camber Changes – We may adjust our camber many times during the season because the grip levels change with the changes in temperature at your track. The tires behave differently when the grip changes and we need to keep up with the changes in tire contact patch area with camber changes.

When we change the camber in our front wheels, we may also be changing the toe, and possibly the bump steer depending on the design of the spindle. If the tie rod end is at the same height off the ground as the lower ball joint center of rotation, then there will be minimal change in toe settings.

This is almost never the case with most spindles, so you need to re-check your bump steer as well as the toe. At the shop, you might test your system to see how much toe change develops from each degree of camber change so you’ll know what to expect at the track with those changes.

Ball Joint Changes – Many times we are involved in bumps and crashes during the season. If you bend a ball joint and need to replace it, be careful not to change the height of the ball joint center of rotation.

If the new ball joint has a different shaft length than the one you were using, there are a couple of things that would change as a result. The moment/roll center would change due to the change in the control arm angle, be it the upper or lower arm.

Also, along with the arm angle change, especially with the upper arm, the camber change curve will change and you might find you will need to adjust your cambers too. If you need to ream the ball joint hole in the spindle, you will be changing the height of the ball joint too.

If you can record the height of the ball joint center from the top of the spindle, then if there are changes in the height, you can adjust the inner mount height to compensate and maintain the same arm angle as before.

Spindle Change – Suppose you bend a spindle and you order a new one that is supposedly the same as the old one. Several things could make that spindle different and you need to be very careful to recognize those differences.

First off, if both the old and new spindles were indeed made from the same jig and to the same dimensions, there is no guarantee that the ball joint taper holes were drilled to the same depth. This is something few car builders think about.

When two spindles are different as to taper hole depth, not only does the moment center change with the arm angle changes, but the bump steer changes too because when the arm angle changes, so too does the instant center height and the tie rod is no longer pointed at the new instant center. The bump steer changes and needs to be reset.

The solution is to measure the old spindle and correct the ball joint height problem with different length ball joint shafts that will put the ball joint back to the same height as before the change.

Other dimensioning that might be different include: the degree of spindle, pin offset, steering arm angle from a top view, and overall height dimension. The degree of spindle is the angle a line through the ball joint centers makes with a line perpendicular with the spindle pin. This can be eight degrees to twelve degrees.

The pin offset is the distance the center of the spindle pin is from the lower and upper ball joint centers. Make sure your spindle measures the same up and down from the center of the pin or your geometry will change dramatically.

If the overall spindle height has changed, the difference could be from the pin to the lower, or upper, ball joint center. This can be corrected with a longer or shorter ball joint shaft and you can determine that once you know the difference.

Your Ackermann will be different if the steering arms are designed differently. In the late 1990’s, chassis builders were putting spindles designed for rack and pinion systems onto drag link systems and those cars suffered. They not only created a lot of Ackermann, they were much shorter than the standard spindle that had been used which was based on stock dimensions.

The new spindles were lighter and this was thought to be an advantage. I was working with a team that had these installed on a new chassis. We just replaced them with custom made light weight spindles made to stock dimensions and had the best of both worlds.

Spring Rate Changes – As we change our spring rates, we could be changing more than just the rates and the handling. A spring rate change means the chassis moves differently than before. If we stiffen the right rear spring rate, that corner will travel less as we negotiate the turns. So, if we have a rear suspension system that is sensitive to movement, then our rear steer will be different.

Suppose we have our rear links adjusted for near zero rear steer with a 250 ppi right rear spring. We change to a 300 ppi spring and the right rear travel goes from 2.25” to 1.875”. That is because we are going stiffer by 17 percent and 17 percent less than 2.25 is 1.875.

We just changed the motion of the right rear link or links by 0.8 degrees or 0.375”. We would need to reduce the front mount heights by half that amount, or 3/16” in order to have the same rear steer characteristics.

In addition to the rear steer, the rear moment center height will change and be higher by the 3/8” difference in travel of the right rear with the stiffer 300 ppi spring. So, we will need to lower the right side panhard bar by the same difference in travel, or 0.375” which is 3/8”. Now we will have made just one change to the car, the right rear spring rate.

Spring Rate Vs. Balance – Another aspect of spring change when you are trying to create a more balanced setup is the relationship of balance to weight distribution. As you change your balance, your weight distribution must also change. If your car is tight from being dynamically un-balance, you would have naturally set your weight distribution to make the car neutral in handling.

As you make spring changes to bring the car into a more balanced state, the weight distribution must also change or the handling will change with each spring change. So, if the car were tight dynamically, you probably would have already reduced the cross weight or bite to make the car neutral in handling. Later, when you make changes that make it more neutral in balance, the car would be loose if the cross weight, or bite, were not increased.

Your car cannot have a constant weight distribution when you are making setup changes that affect the dynamic balance. Teams who try to maintain a set cross weight or bite number will never realize the benefits of working towards a dynamic balance and a better setup.

Shock Changes – We often make changes to our shocks as the season goes along to try to tweak all of the performance out of our cars. That is OK, as long as we don’t create problems and then not realize how they happened.

An example is this. Say your car was tight getting into the corner and you install a “tie-down” shock on the left rear and that helped. Then later on, you find that the right front shock is too stiff on compression, or the spring on that corner is too stiff, so you put on a softer shock and/or spring.

The tight-in condition is solved, but now you are loose in. Remember that you installed that shock on the left rear that was stiff in rebound. You now need to remove that crutch and install a normal rated shock to bring the car to neutral on entry.

Panhard / J-bar Adjustments – When you make changes to your panhard bar (a term I’ll use for both a panhard bar and a J-bar) for height and angle, you are also making changes to the attitude of the car. This may have an effect on the rear moment center height as well as the rear steer characteristics.

If you change the angle of the bar, but not the average height, then the static moment center will not change, but the dynamic MC might change. When dirt teams put more angle in the bar with the left side chassis mounted higher than the right side rear end mount, the rear of the car will jack up and be higher through the turns than before and the rear MC will then be higher.

This will loosen the car just from that change even though you did not change the static MC height. For an asphalt car, when you lower the right side chassis mount below the level of the left side rear end mount, there is a force upwards on the chassis mount that reduces the travel in the right rear corner. Now the end of the bar on that side is higher through the turns and the MC is also higher resulting in a looser car.

When you make changes to the angle or rake of the panhard bar, you are also changing the dynamic (part of the setups dealing with turn attitude) MC height and therefore the handling of the car. Many teams want to know why other teams do this and it might be because it may free up a tight car. There are better ways to free up a tight car.

Rear Link Angles – Changes to the rear link angles mostly change the motion of the rear wheels fore and aft when the car rolls and changes height through the turns. The result is rear steer or lack thereof. But that’s not all that is happening. A change in the fore and aft location of the rear end can affect the loading on the tires when using bird cage mounts.

If the car uses bird cages to mount the springs to, the height of the spring mount changes as the bird cage rotates due to chassis travel. This is because the top and bottom links are set at different angles and this causes the top and bottom link mounts on the bird cage to move in opposite directions

When the bird cage rotates, the mount for the coil-over moves vertically. The change in handling you experience after a change in link angles may well be a result of re-distribution of loading on the four tires. Think out how link changes affect the shock/spring height.

Rear Spring Angles – Also associated with dirt cars, when a team changes the rear coilover angle, they do two things at once. One, the greater angle reduces the spring rate the car feels. Imagine a spring lying on its side. It would not be able to support anything, so the more angle the spring is mounted at from vertical, the less load it can carry and it becomes like a softer spring.

The other thing that changes is the rear spring base. When we move the upper mount of the coil-over in closer to the centerline of the car, the distance between the upper mounts of both right and left coil-overs becomes less. A more narrow spring base increases the roll rate and decreases the roll resistance for the rear suspension.

The combination of a softer right rear spring rate and a shorter spring base both contribute to less roll resistance and therefore a tighter car. If you move the upper mount of the right rear shock in and also increase the right rear spring rate, you might not have changed anything related to the dynamics of the car because they cancel each other out.

Weight Placement Changes – When you move weight around in your car, you might be changing the front to rear weight percentage. We know from doing calculations that in order for the weights to end up correctly after load transfer has taken place, we need to start with a certain static weight distribution dependent on the front to rear percent.

If we can calculate, and we have, the load transfer for a balanced setup, there needs to be a defined weight distribution on the four tires that will yield the correct loading on the tires at mid-turn, steady state. When we move weight around and change the front to rear percent, we must also change the cross weight, or bite.

More rear percent requires more static cross weight, and less rear percent needs less cross weight. So, as you make changes to your front to rear percent, know that you also must change the static weight distribution (cross weight) in order to maintain the handling balance.

Conventional to Bump Setups – I saved this for last for a reason. This could get very involved, but I will point out a few things that could go wrong with this transition. First off, your cambers will need to change dramatically due to the greater travel of the wheels in bump. You’ll have to find what camber works for your tires at your track.

Your overall setup must change because you are now running much stiffer spring rates at the front causing much less front roll angle. So you must “stiffen” the rear too. By stiff, we mean made to create much less roll tendency, like at the front.

You can do that with spring split (stiffer right rear spring than at the left side), a higher panhard bar setting, and overall stiffer rear springs. Be careful not to overdue this process. You just want to match the roll angle desire of the front, not go past it into a stiffer system. Many teams will over spring the right rear and that creates its own problems.

Your shocks must change too. When you install stiffer springs, and bumps are stiff springs, you must control those stiff spring rates with much more shock rebound control. Even the right rear must be re-evaluated for shock rates when putting that 300 to 400 ppi spring in place of the 200ppi spring you used to run.

And as we pointed out above, if the right rear moves much less due to the stiffer spring rate, then the rear steer will change and we need to move the trailing arm mounts to compensate and correct the rear steer.

Conclusion – So there you have it. Now you know some of the things that can go south when you make changes. We hope now you can better think out your changes and be more aware of the other settings that might be affected.

We are not trying to say changes are not good. We encourage changes that can make your car better. Racers are all about changes and without that aspect of this sport, many would just quit. So as you go through your changes on whatever part of the car you are working, think more globally and imagine what else might be affected.

The post What To Keep Track Of appeared first on Hot Rod Network.

I’ll start out by saying that in life, there are things that happen that are out of our control and people die. It’s always been that way and always will be that way. And then there are those things we can somewhat control, and fire is what this discussion is all about.

A young man with a wife and baby died in Ohio this year in a dirt car that turned over and caught fire. I don’t know the exact details of this, nor do I really want to. It’s bad enough just knowing the outcome. But like many things that happen, if we learn from this, maybe we can prevent someone else’s family from having to go through what this young man’s family is going through.

Gas and alcohol fires are hard to put out. They can burn for many minutes and that is too long when a driver is trapped or unconscious inside the car. We need to employ specialized equipment to quickly put those fires out and most race tracks don’t have the proper tools.

What we know about racing safety at this point in time is that we have improved the knowledge about how to build better and safer cars, seats, seat belts, helmets and head and neck restraints. Even the way race tracks are built is better today in some cases.

We’ve gotten better at making fire resistant suits and undergarments, initial thanks going to Bill Simpson who recognized the need some fifty years ago. Having all of that available, it is the choice of the participant how much money they want or need to spend. A full blown fire suit with all of the things that go with that might have saved this man from life threatening burns, but if he were in the fire for too many minutes, asphyxiation alone would do him, or anyone, in.

I think we need to talk about how as a sport, we can educate the race track management on ways to equip themselves to be able to respond and put out a fuel fire more quickly. I personally have seen a situation where a car caught fire, the driver got out OK, but the track crew could not put the fire out. It burned for over fifteen minutes.

They used over a dozen fire extinguishers and still didn’t make a dent in the fire. If the driver had still been in there, so long buddy. And this was at a well known track where racers from all over the country come to compete, not that it should matter.

I guess it’s all about investment and education. There is equipment available out there that turns water into the foaming agent that knocks out a fuel fire. It fits easily into the back of a pickup truck, goes into action quickly and is easy to use. It just costs money.

It only takes one instance like this to tell us that we don’t have all of the bases covered in stock car safety. Admittedly, these occurrences are rare, probably more rare than drivers dying from neck injuries. So, do we just roll the dice, or do we do something about it?

And whose responsibility is it anyhow? Racers commonly think it won’t happen to them, whatever it is that might go wrong. I guess race track managers hope it won’t happen at their track. But even the possibility of this should scare the crap out of any person who is responsible for others safety.

Maybe there needs to be a certification process, voluntary everyone will say, that requires watching a video of a race car fire where someone does not make it out alive. I’ve seen bad fires where the driver got out of the other side of the car from where I was watching and survived. But from my view, the fire burned and burned and we couldn’t tell if the driver was in there burning up or not. It was, in short, horrible.

Come on racing industry, let’s get our act together and at least prepare for things like this. There will always be car fires as long as we use volatile fuels. We need to match the threat with the proper tools and associated education to use those tools. Now is the time for the safety companies that make and sell these types of equipment to go out there and sell, sell, sell. We now know fire extinguishers will not work in every situation.

Ride Height Article Comments

Hi Bob,

I just got through reading the article on ride height tech in the July issue of Circle Track. Very good article! I do have a couple of questions. My algebra is not too good. I do not see how you came up with the number 0.89 rounds per percent of crossweight.

This would only work with the spring rates that you have picked 200 lf, 250rf, 175 lr, 350 rr. .If you use different spring rates you would have to refigure the multiplier, right? Keep up these wonderful tech articles!

Thanks, Ray.

Ray,

What I was describing was a process. Of course you would come up with different numbers for different spring rates. But try to see how I did it and came up with my numbers. I could have used X’s and Y’s, but that might be more confusing.

When you plug in your numbers, do the same process as I did and you’ll come up with your percentages to use. This is a way to make changes to weight distribution, i.e. cross weight, that is quicker and easier. I have watched, in pain, a team try to change scale weights while maintaining ride height where it took an hour. I had to leave the shop.

No Ride Height Rule

Hello Bob,

I just want to say I have read everything you have written. But my question is, we are going to try the BBSS setup this year and the track we race at no longer has a ride height rule. So, where should I start with my ride heights or does it really matter?

Because once I get down on the bump stops my shocks will keep me there, but what about the rear? I run a Latemodel sportsman as the class.

Thank you, Richard.

Richard,

First off, you might consider dropping the BB part of the Big Bar, Soft Springs setup. Most knowledgeable teams have gone to using much smaller sway bars with the bump setups. Just thought I would throw that in. It might save you some time and money.

Your ride height can be anything you want it to be as long as you can move the car around the pits and into and out of the trailer. But do develop a set ride height so you can go back to your static camber settings and weight distribution.

If you don’t establish a fixed ride height for the shop and at the track, you’ll never end up with the same cross weight number or cambers. It is important to maintain certain measurements like panhard bar height, trailing arm angle, etc.

If you don’t have a fixed ride height, then how will you ever check or change those numbers? And, the rear might need to be close to the height it will experience down the straights. That way, you’ll be able to set your panhard bar and trailing arm heights accurately and repeatably.

While We Are On The Subject

Bob,

Not sure if this is enough info? I have a question about where to set my ride heights at the track I race at as they did away with the ride height rule. We are running bump stops on a late model sportsman. Thank you.

Richard Oakley

Richard,

See the above. Why did I put this in here? Because I like you to know I try to answer every email and letter.

Seminars Available?

Is there a seminar I can take with Bob to get the basic knowledge to set up stock cars?

Thank you, Brian Here.

Brian,

These articles we post every month are themselves seminars. But I know what you are asking for, a live performance. There is a seminar that Circle Track promotes and we had a lot of success last year helping put it on. It is the GRIP Seminar and it takes place in early February in Mooresville, NC at the famous Dale Earnhardt Inc. building.

We are very proud to have had the opportunity to help out with this because of all of the seminars I have been to, including my own seminars, this one provides more information and gives the attendees a chance to ask questions of some of the most knowledgeable presenters there are.

Yes, I participate in the seminar with my own segment as well as helping out with others presentations when I can. These seminars are not cheap, but compared to the alternative of spending years trying to figure all of this out with trial and error, the cost is low.

Adjusting My Ackermann?

Bob,

How about offering a discussion about recommended methods for adjusting (or changing) the Ackermann on a modified type racecar with stock type steering? We’ve done it for years but I’m just not comfortable anymore with bending and/or changing the length of stock spindle steering arms.

You are in luck. This issue has an article dedicated to that subject and tells how to change the Ackermann. I understand your concern, and in the article I advise racers to be careful when altering cast parts, or any part for that matter.

There are after-market drag link kits available from well known suppliers that can solve your problem. If you can determine what drop you need in order to arrive at the correct tie rod angle from a front view, then you can choose the right drag link to connect those tie rods to.

G-Body Spindles

Bob,

My son and I have raced since he was eight and he is twenty eight now. We were running a G-body on pavement with two track championships. The track is going to be changed to a dirt track.

We have read all of your articles on the G-body. We have stock spindles and with all allowable modifications and the I/C and bump are horrible. In your writings you suggest Impala spindles that are taller with better Ackermann etc.

If the Impala spindle is the only way to go, please let us know what year. Would we still need taller upper joints, etc. Any help be greatly appreciated .

Jake and Thomas McGrath

Jake and Thomas,

I don’t remember ever suggesting using Impala spindles. I did hear of racers with those cars using the older Camaro spindles because they were taller and provided more upper arm angles. If the Impala spindles do that, then have at it. I think the dimension from the top of the spindle to the bottom was 9 ¼ inches for the early model Camaro and only 7 ¾ inches for the later cars like yours.

The bump steer must be corrected with a different drag link and that may also improve the Ackermann that might be present in those cars. We don’t necessarily recommend cutting and welding on cast parts or the stock drag link, but that has been done by other teams.

One of the most significant gains you’ll have is getting your moment center to a better place. I have found that when we can get more upper control arm angle, either by using taller spindles and/or taller ball joints, the car turns much better, and you need that on dirt as much as on asphalt.

If you have comments or questions about this or anything racing related, send them to my email address: chassisrd@aol.com or mail can be sent to Circle Track, Senior Tech Editor, 1733 Alton Parkway, Suite 100, Irvine, CA.

The post Standards of Racing Safety and Q&A with Bob Bolles appeared first on Hot Rod Network.

The term Steer – Steer refers to additional steering that takes place when you steer your car. The common name for this is Ackermann, named after the fellow who discovered this helpful geometric phenomenon. Helpful in some cases, but not in short track racing for the most part.

We have talked long and hard about Ackermann, but here we will tell you how to check for it and how to adjust your car to eliminate most of Ackermann just because you don’t need it. First a short refresher course on what Ackermann is along with a little history.

Ackermann use to be popular. That is because in most setups for asphalt and dirt, there was less use of the left front tire in years past. It had less loading on it through the turns. Ackermann actually helped that lightly loaded tire gain grip. In today’s racing world, the dirt and asphalt cars are more balanced in their setups and the LF tire does much more work.

This trend has made the dirt cars more consistent and faster under most conditions. With the asphalt teams, now that the LF tire is gripping more, it needs to track along with the RF tire or they will end up fighting each other and the car will lose front grip.

Just What Is Ackermann – When we have Ackermann effect present in our steering design, it means that the amount of toe-out increases as the steering wheel is turned and with Reverse Ackermann, toe is reduced. There are different static settings for front end toe that are dependent on the size of the race track, the banking angle, and the type of tire used.

Most short track stock car teams use toe-out to stabilize the front end and keep it from darting back and forth across the track. Conventional wisdom tells us that the car will need more static toe-out for the smaller radius tracks. At bigger racetracks of more than a quarter-mile, much less toe-out is required. The amount of toe-out used typically ranges from one-sixteenth to one-quarter of an inch.

The truth is, we need very little Ackermann effect in most situations when racing on an oval track, be it dirt or asphalt racing. Even on very tight quarter mile tracks, the LF wheel will only need an additional 1/16 inch of toe over the RF wheel to correctly follow its smaller radius arc. That is 0.112 degrees or a little over one tenth of a degree.

You can imagine my reaction when a racer tells me that they only have a couple of degrees of Ackermann in the car. A degree of Ackermann equals ½ inch of toe for an 85 inch circumference tire. So, if we have two degrees of Ackermann in our steering systems that would equal an additional inch of toe when we turn the steering wheel. We would never think of setting an inch of static toe in our cars and then go racing.

Checking For Ackermann – To check to see if, and how much, Ackermann you have, you can use either simple string or if you have it, a laser system. The process is the same, just the tools are different.

Aim your wheels straight ahead in the shop, or anywhere for that matter. String along the sidewall of your tire making sure not to go over any lettering or other extrusions. Go out ten feet in front of the axle and place a piece of tape on the floor under the string line.

You will carefully lay the string so that it just touches the edge of the sidewall in the front part of the tire while having someone hold the string wrapped around the side of the rear part of the sidewall. Bring the string down to the tape and make a mark with a felt tip pen.

Go to the other side of the car and repeat the above for the left front tire. When you have two marks, one for each side, turn the steering wheel the same amount as you would at the track going through mid-turn. Then repeat the string method for both sides.

Now you have two sets of marks, one set for the right wheel and one for the left. Measure the distance between the marks for each wheel. If you measure the same on each side, you have zero Ackermann. The angle of the tires is exactly the same when the wheel are turned.

If you measure a half inch more for the left wheel than the right wheel, you have gained about one 1/8 inch of toe over what you started with. This is the most you’ll ever need and might be good for very short ¼ mile ovals. For longer, faster tracks, you’ll want less.

When using a laser, you will do the very same procedure, except you’ll be using the laser instead of a string. Attach the laser to the hub and point it at a target ten feet in front of the axle, or down at tape on the floor. You’ll make marks and measure between them.

Correcting For Ackermann – If you find that you have too much Ackermann, or if you have Reverse Ackermann where you lose toe (i.e. the left measurement is less than the right side measurement) and you want to correct it, here are some methods for doing that.

If there is excess angle in the tie rods from a top view (the inner mounts rearward of the outer mounts) there will be Ackermann present. Reducing this angle reduces the Ackermann and fixes it for turning both left and right, like you would do in a road racing car or a dirt car on an oval track.

For rack and pinion designed steering, the correct way to adjust for Ackermann is to move the rack forward or aft. To reduce Ackermann, move it forward and to increase it, move it rearward as in the case of Reverse Ackermann. Make sure both steering arms are the same length when making this change.

For drag link steering systems, we suggest a similar fix. Instead of moving the rack, we move the part of the drag link where the tie rods are attached forward if there is too much top view tie rod angle. This is not easy to do and usually involves installing a new drag link designed to place the inner tie rod mounts more forward.

Some teams have taken it upon themselves to re-design this part, but we don’t recommend bending or cutting and welding steering parts or doing something that might be unsafe. It is up to you to make sure any changes you make to your car are safe.

In past years, race cars fitted with the drag link steering systems used spindles that had steering arms with two holes. This was intended to be used to adjust for Ackermann by either using the front holes, or the back ones. Teams that experimented by using the back hole on the left and the front hole on the right learned really quickly that this produces a bunch of Ackermann and the car refused to turn after that change. Please don’t do this. Small changes in the length of the steering arms have a pronounced affect.

Again, the above fixes are perfect for road racing cars and dirt cars where you would be steering in both directions and need to have the same toe settings whichever way you steer. But for race cars that only turn the steering wheel left, there is an easier way to go about this.

For a short track car that always turns left, we usually can lengthen the left steering arm and that reduces the Ackermann effect. For stock type of cars with cast spindles, you’ll need to cut and add material and weld back together. We would never recommend doing something that would be unsafe and you will need to determine if any changes you make are safe.

For most Late Model cars, the spindles are made with slotted steering arms, sometimes on both sides. You could lengthen the left arm and/or shorten the right arm length to reduce Ackermann. Remember that small changes in the length of the steering arms make for a big change in Ackermann.

The post How To Check For And Adjust Ackermann appeared first on Hot Rod Network.

Mark Whitney is an industry leader in researching automotive and race car safety. Several years ago he provided the following information so that we could educate the racers. He wanted to help them understand the mechanics of crashes and how we can construct our environment so that we have a better chance of surviving in the event something goes wrong. It’s time to get re-educated.

Seat Mounting – The seat should be mounted to the roll cage or structural member of the frame. It is always better to use manufacturer supplied mounting rails, these are specially built for your seat. These will properly mount the bottom front and bottom rear of seat. These Seat rails should be bolted to the seat with Grade-8 3/8″ bolts, heavy duty large flat washers and lock nuts. Space the bolts as far apart as possible to properly distribute the load.

When securing the back of the seat, tie it into the horizontal tubing that runs behind the seat. Instead of bolting through the tubing, it is better for strength purposes to weld-on a bracket and then bolt through that. The bolts should be bolted up and down (vertically) to place the bolts in shear.

Use a bracket that will support the entire width of the seat. Spreading this load will provide a more secure mounting. Use a minimum of 4 Grade-8 5/16″ bolts, heavy duty flat washers, and lock nuts spaced as wide as the width of the seat. Again use a manufacturer supplied bracket, whenever possible, to connect the seat, the rear bar and mounting flange.

Padding/ Door Pads – In an accident, one of the first areas of the car that your body will hit is the door bars. It is a large area tight up to the seat and well within reach of your swinging arms. Roll bar padding on these bars will help, but you still can slide between the bars.

Most teams are using full sheet door pads. This is a piece of fire retardant material that has an impact dissipating foam laminated to the back of it. This provides a flat surface for any body parts to impact into.

Belts and mounting – A key to a driver’s safety in the cockpit has a lot to do with the quality, mounting and care of the seatbelts. Here are a few concepts to think about when buying, installing and using seat belts.

1) Better Belt Materials – Early seat belts were made from cotton webbing. As technology advanced it was found that nylon was a better choice for longer life and higher strength. In the last 5-10 years polyester and combinations of materials have made their way into the market of competition seat belts.

These materials have been preferred because of the small amount of stretch compared to the average nylon stretch numbers. There are quality nylon belts on the market and the price difference between nylon and polyester does not always gain the stretch advantage for the price a racer is paying.

2) Keeping the belts as short as possible – As we just mentioned all belt webbing will stretch. The amount the belt stretches is a function of the tension load placed on it and the length of the belt this tension is applied to. The more the belt stretches the further the driver moves in seat and more likely they are to be injured. Shorter belts will lessen the stretch. 3) Do Not Use Sternum Straps – When they were first developed, Sternum Straps were used to keep the shoulder belts closer to the middle of the chest and keep them from sliding off the shoulders. What has been found since then is that these straps can create neck injuries.

As the driver’s torso moves forward, in a frontal impact, the shoulders slide on the belts and the sternum strap moves toward the neck. Proper mounting and the use of short belt lengths will accomplish the goal of keeping the belts properly on the driver’s chest.

4) Proper Mounting Angles and Hardware – The SFI Foundation has an article on their web site (www.sfifoundation.com) detailing proper belt mounting methods, angles and procedures. There are other articles and diagrams on the web, but SFI has such a wealth of safety knowledge on their site that it is worth the look.

5) Certifications and Age – Any quality belt system will have a certification tag. This is the manufacturer stating that the belt meets the minimum standards set forth by a certifying foundation under a certain specification.

Most belts in America, and quality belts from overseas, will have an SFI tag. Another tag to look for on the belt is a date of manufacture. It is commonly held that a set of belts should not be used more than two years after their date of manufacture.

Knee knockers and Leg Braces – The largest mass of the driver’s body that is unrestrained are the legs. During an accident, with no boundaries, the driver’s legs are free to hit anything from the transmission tunnel and shifter handle on the right side of the cockpit to the door bars on the left. To control the driver’s leg motions side to side it is important, when possible, to utilize leg braces and a steering column mounted “knee-knocker”.

The leg braces are run from the front of the seat on the sides of the legs to the front firewall or as far forward as reasonable. The braces should be made from a substantial aluminum. The edges of the braces should be bent over, not only for strength, but also to eliminate another opportunity for the driver to cut themselves.

Finally, if there is room, a “knee-knocker” should be installed under the steering column or to the front of the seat. Both options work well, but still consider that this should not be mounted absolutely rigid, unlike the leg braces, the knee-knocker is designed to keep the knees apart and slow down the motion of the legs. If the knee-knocker is mounted absolutely rigid, the leg can wrap around it and create injuries.

Below the dashboard, the only things to stop the driver’s feet are the pedals. The pedals need to be mounted solidly to the chassis and the pedal faces themselves need to be thick enough so as not to slice into the driver’s foot or leg if the leg were swung that way in the event of an accident. A thin pedal face is lighter, but it can act like a knife blade when the side of a driver’s shoe comes in high-speed contact.

Head Nets – Head Nets have become a visual staple in many series of motorsports. They first appeared as an additional way to control the motion of the head and arms inside sprint cars. They were then utilized in the stock car realm for protection of the driver’s head. They were used for the right side excursion of the head when the passenger side of the car impacted the wall.

The window net that is so common provides little protection for the head contacting the track wall in a left side impact. The addition of the left side head net provides an extra barrier. With the advent of seat-mounted head surrounds, the need for the head net is reduced.

Mounting of Cockpit Components – In professional racing, the days when a racecar was a stripped down passenger car have been over for a while. Each Nextel Cup racecar is now a purpose built vehicle that has systems and infrastructure built in that enhances safety.

This is not true of the common stock class series where we must ourselves carefully provide a design that is safe. When designing the cockpit of your race vehicle it is so important to look at the mounting of each accessory that goes into the car, in regards to what will happen to that piece if you are involved in a wreck.

One of the areas of most concern is the mounting of the tachometer. This is an accessory that is often attached using hose clamps. Anything that is added beyond the normal parts of the interior and roll cage should be bolted to a roll bar with bolts that sustain it in case of a wreck. Other cockpit accessories that are commonly miss-mounted include the coil, on-board computer, radio, drink bottle and fire extinguisher. Once the basics of cockpit safety are reviewed, it is then time to look at more advanced levels of safety.

6 and 7 Point Harnesses – The most basic racing seat belt system is 5-point system with two shoulder belts, two lap belts and a submarine belt. To gain addition body control, the 5-point system can be changed by replacing the single sub belt with two individual belts to control the motions of each leg. This system is called the 6-point harness.

The 6-point harness system is a vast improvement in body control compared to the 5-point, but there are still another way to increase a driver’s body control. In the typical 6-point system, the leg belts snake through a loop in the lap belt and hook into the shoulder belts. This belt arrangement puts an odd angle on the direction of force for the tightening of the shoulder belts.

One way to keep the benefits of the leg control of the 6-points and keep the belts in an optimum alignment is to add back the single sub belt so that the shoulder belts pull against that single sub belt. This belt system is offered by many manufacturers.

Conclusion – The best way to sum up this article is with a quote heard at an SAE Motorsports Conference by noted racing physician Dr. Terry Trammell, “Safety is not a Driver’s Right; it is a Driver’s Responsibility.” It is important to understand that just like your race engine, your safety equipment is a system in itself. Any addition to your safety program must not only consist of high quality products, but must also fit well into your overall safety system.

The post Cockpit Safety Tips appeared first on Hot Rod Network.

Race car safety includes a number of areas that we need to be concerned with. We have the actual chassis design, the various add-ons to that chassis that are available, the seat and restraint equipment, our fire control systems, the driver’s apparel, and the design of the race track that combined influence our safety. Those, along with the team’s safety awareness all add up to what should be a high level of survivability.

At some point in our preparation for going racing, we need to address, review, analyze, plan and enact safety measures that will help prevent serious injury or death in the event of a crash. And we can do that at any time of the year. Here are the major areas of interest concerning race car safety.

Basic Chassis Design – One of the most critical areas of concern for chassis design is stiffness. Over the years, racers have been seriously injured and killed by the force of impact with the wall or other objects. The leading cause of death in these types of crashes is basil skull fracture. It is basically the same injury suffered by someone who is hung by a rope.

In short, death is caused by the body stopping in a very short distance over a very short duration of time, and the head continuing forward at the same high rate of speed. The neck is not designed to contain this extreme force. The tendons that hold the skull and vertebrae together break and cause extreme damage to the brain stem, spinal cord and blood vessels.

This is not a pretty picture, but you need to understand what happens and decide you don’t want that happening to you or a loved one. The impact with a wall or light pole or other fixed object while traveling at a high speed generates a lot of energy. The more time it takes for the speed to be reduced to zero, the less G-forces that are transmitted to the drivers body. Something must give and move in order to extend this time sequence. Either the wall (or whatever is struck) must move or give way, and/or the car must crush. It is the crush factor, be it the object struck or the vehicle, that helps us survive.

In past years we have seen some horrific crashes that were survived or not due to the level of crush factor. In the truly stock race cars of the 1960’s and 1970’s, speeds were reached that equal or exceed today’s stock car speeds. Drivers hit the wall at very high speeds with much less adequate protection than we had in the 1990’s, but survived. Why?

Cars of yesteryear were built using the original stock chassis. These frames were stamped into a shape that was convenient for attaching the body and suspension parts and there were lots of curves and hardly any straight pieces. Curves in steel parts easily bend. So, as these cars struck the concrete walls, the chassis bent and absorbed much of the energy of the crash. Injuries and deaths started occurring when we started fabricating special chassis for racing that had more stiffness using straight lines and less curves.

Today there are still many race tracks that have naked concrete walls without energy absorbing coverings. All of the crush factor must be designed into the race car chassis if we expect to dissipate the energy of a crash. Race car builders must be aware of this need as they design a new chassis. If not, the driver of that car is at risk.

Intrusion Protection – One of the more rare injuries we see with race cars is when outside objects protrude into the car and injure the driver. The object can be a drive shaft separated from another car, a lost bumper, the end of a guard rail, a tire and wheel that has come off another car, etc. We need to provide protection from intrusion with our chassis design.

Plating the side bars help prevent side intrusion and this plating should extend forward to protect the front of the foot box. Netting beside the drivers head helps keep the head and arms inside the car, but can also keep objects out of the cockpit too.

Remember to plate the underside of the seat along with welding bars in the windshield area to keep out flying objects of a larger size. Seal and inspect often the firewall and interior sheet metal seams that are needed to keep out dirt, exhaust gases and flames.

Padding – All exposed tubing, steering column, and other hard equipment inside the cockpit must be padded with dense cell padding material intended for race car use. Foam insulation type padding is not stiff enough to dissipate the energy of a flying arm or leg. The stiffer material may seem a bit hard to the touch, but when hit hard will absorb the energy without collapsing, or squashing down to the bare metal.

It is a similar concept as helmet foam. That medium is hard to the touch, but conforms to the shape of the head on impact and absorbs much of the energy. Attach padding to all of the exposed roll bar tubing that is within reach of the driver’s arms and legs. An especially neglected area is between the legs along the steering column. The mount, bolt ends and shaft all can cause serious bruising or fractures of the bones if not adequately padded.

There are pads now available for the door bars, seat sides and back, head restraints, and steering wheel center post. The more padding you can use, the safer you will be and the more comfortable too when utilizing seat and leg padding .

Seats and Accessories – The racing seat along with the seat belts, arm restraints, netting and head and neck restraints are the primary line of defense against personal injury or death in a race car. Aside from fire protection, your first thought and concern should be to install a quality seat that fits your body perfectly. Then fit seat belts that will hold you in the seat properly along with netting that will contain your extremities.

Generic seats are cheap and I understand racing budgets. If you cannot afford a custom seat built to your bodies dimensions, then at least buy a size that fits snug and/or fit proper padding foam designed for seats so that you cannot move around in the seat.

When I raced karts, my seat was shaped so that I had to turn my hips to enter the seat and then the hips were locked in tight when I was fully in. This provided a lot of support and reduced the movement from the 3+ G’s we experienced while road racing.

I would be bruised along the sides of my hips and legs from the side force, but never felt like I was not firmly in the seat. As you go through the turns, the lateral loads must be contained by the seat against the body, and with some seat designs, the shoulders.

There is a proper way to mount the seat belts and every manufacturer has specific instructions on how to do that. Read and follow the instruction. If you are the driver, do a visual inspection of the installation before you get in the car and drive it. The nets should be tight with no slack in either the vertical or horizontal direction. Memorize where the release levers or cords are located to release the nets.

Fire Control – The danger of fire in stock cars has been greatly reduced, but not entirely eliminated. With the introduction of fuel cells, fire suppression systems (fire extinguishers), fire suits and fire proof materials, the risk of getting burned is much less than ever. The level of protection though is up to the driver.

There are different levels of fire suit protection available with escalating cost as the level increases. Opt for the best system you can afford to risk. That is, imagine the worst case scenario and design your system so that you will survive. Make regular inspections of the fire control system a part of the maintenance schedule and put it on a checklist. I see teams overlook this item a lot.

Consult with the experts to see if there are new designs that might be more efficient or cost effective for your type of racing. At year’s end, remove and inspect all of the components of your fire control system. Make sure the nozzles are clear and the tubing is not crushed or bent. Have the bottle inspected by the manufacturer and refilled if necessary.

Safety Apparel – What will allow you to survive a fire is the clothing you wear. Each racing suit, glove and shoe has a fire rating. That is the measure of how long you can go before you get burned. In a best case event, the car catches fire and you exit in ten seconds or less. Good for you. But wait, there are other circumstances that may extend the time it takes to exit the car you might not have thought of.

Here are some mitigating circumstances that might occur to delay your exit of the car when it is engulfed in flames:

1) loss of sight, from smoke and/or flames, that is needed to find the window net latch, etc.,
2) the driver’s side of the car is against the wall or other cars necessitating exit out the “passenger” side of the car,
3) the car is upside down,
4) you forget to unhook the radio cord, air hose to the helmet, your head and neck support,
5) you are stunned from a high impact with the wall or other cars and must regain your awareness, the worst case being knocked out.

The problems that can arise will add seconds to the time it takes to exit the car. The best case time of ten seconds or less now turns into 30 seconds or a full minute. Do this exercise, sit and look at your stop watch and imaging you are in a burning race car and get the feel for how long 10 or 30 or 60 seconds is. I just did that here at my desk and I can tell you, a minute is an eternity. Only the best rated suits will protect you for that period of time.

What greatly increases the protection time is fire rated underwear. The Nomex brands really help and the carbon-x or similar designs are incredible. A SFI rating becomes up to twice as effective with proper underwear. All of this may add up to a higher cost or less comfort in hot weather, but imagine for a second the alternatives. You could end up lying in a burn ward for upwards of several months with the loss of income for your family, and permanent disfigurement.

Track Design – The conditions at your track can have a profound effect on the safety level for not only the drivers and crews, but spectators as well. We need to be concerned about how our local track prepares for problems. It is your responsibility to evaluate your race track for safety and make known any concerns to the owner.

Every track must have emergency personnel for trauma, fire fighting, and extrication. An ambulance with trained medical technicians is needed and a dedicated fire truck should be on hand. If you have to wait on an ambulance or fire truck to be dispatched to the track from the community, especially in rural areas, you can bet you’ll be in a world of hurt if you are seriously injured with internal injuries and/ or burns. Time is of the essence in an emergency and safety personnel should be at the track, not at the coffee shop down the road.

The design of the facility can be improved with just a little forethought. The ends of concrete walls or steel guard rails must be protected. Large, used commercial tires offer a lot of protection from impact. Plastic barrels filled with sand or water also provide impact protection. Dirt berms and restraining barriers that will contain the cars and prevent entry into the pit area also help to prevent injury to bystanders.

It might be a good idea to form a safety committee at your track. It can be composed of a combination of track officials and race team members. Working together, you can address any safety problems before they arise. It is in all of our interest to race as safely as possible.

The post Race Car Safety appeared first on Hot Rod Network.

A few years ago, I wrote some comments on what I thought about sealed crate motors. It was titled “The Sealed Motor Fiasco” and it appeared in the December, 2007 issue of CT. What I basically said was that sealing these motors promoted cheating.

I firmly believe that the crate motor program is a good one and the sport may well be better off today than it would be if the crate motors had not come along. That being said, we still have a problem with cheating.

I was chastised in an email from the head of a major manufacturer’s sealed motor program for what I had said and how I had “told them how to cheat.” This person was oblivious to what was happening in that program, but became much more aware a short time later. Read on.

When I wrote the 2007 opinion, I had less knowledge than I do now. I recently talked to a long time tech official that I won’t name or tell where he worked. He offered two very important things.

One, a racing friend he knew was visiting from a far away state. He was looking for a “good” crate motor and at the urging of the official (to see what would happen), called a well known engine builder who was allowed by the local rules to re-build sealed motors in this particular state.

Once the engine builder found out the racer was “not from around here,” he outlined what would go into this motor he offered and that the final price was $11,000. Numerous illegal parts were to be used, and it would be all sealed up when they were finished. This is just one example of what has been going on for some time now.

The second point made was that since the sealed motor programs have been utilized, if a seal is broken either by the crew or let’s say an official who wants to check the motor for legality, the racer must then take that motor to a certified sealed motor re-builder to be re-sealed at a cost. And it’s not cheap either, usually the cost of a full re-build going for $1,500 to $2,000.

So, not only does the sealing of the motors tell an official that the motor is “legal” and he doesn’t need to look inside, he cannot break the seals to inspect the motor even if he wanted to lest he cost the team a couple of thousand dollars. I never considered that the officials actually cannot inspect these motors even if they want to.

Ironically, just a few months after the original Fiasco piece came out, the two-time national champion of a major sealed motor Dirt Late Model series that was sponsored by the above un-named manufacturer was caught with a cheater motor at a national event. The proof is in the pudding.

Let’s look at how the crates are doing against built motors. Our very own project asphalt Modified that runs in Florida and is owned and setup by Dick Anderson is running a crate motor against built motors and was granted a 100 pound weight break until he started beating the other cars regularly. As of this writing, his driver, Josh Todd, has eight wins in a row.

The difference in power between Dick’s crate motor and the built motors is around 100-150hp depending on how much money went into the built motors. The equalizer is the tires. These cars run on 9 inch Hoosiers and a lot of power can actually hurt you.

The only place you can go full throttle is past the flag stand and that catapults you into the corner which can ruin your corner performance. Dick’s car handles really well and doesn’t need a lot of power to go fast. It evidently doesn’t need the 100 pound weight break either because the officials took that away from him several races ago.

The sealed motors can work and do well against more expensive motors in some cases. When done the way they were intended, they save the racer money and bring more racers to the track. The smart tracks allow a mix of crates and built motors with differences in weight to equalize the field.

I am in favor of whatever can bring up the car counts, so go for it. Try to make it an equal playing field and just enjoy the show. But I’ll say it again, can we please un-seal these motors once and for all?

If you have comments or questions about this or anything racing related, send them to my email address: Bob.Bolles@SORC.com, or mail can be sent to Circle Track, Senior Tech Editor, 1733 Alton Parkway, Suite 100, Irvine, CA.

Racing Is Fun Comments

Hi Bob,
I was sitting here in a Charlotte hospital after having knee surgery reading your editorial on “Racing Fun”, and couldn’t agree more. I raced for over 25 years and it was for the most part just like you said.

When we started in the late 1980’s the car counts were through the roof and they were sending 10-15 cars home so you had to be on your game. Just like you said we thought for sure the fast boys were cheating, but then after buying a car built from one of the best chassis builders all the pieces started coming together.

This builder showed us the way to a properly set up a car and how important it was to keep checking it every week. Before you knew it we weren’t the car going home. The following year we were in the hunt and qualifying, through heat races, with the fast boys every week, and finishing most features in the top 10. By the third year we were winning races and WOW that was fun! Keep up the great work,

Roy Ethier, Newton NC

Roy,

Thanks for sharing that. Racing is not unlike any other endeavor we undertake, we get out of it what we put into it. That’s not to say racers don’t work hard, they do. But we all need to work smart and we try to share what we have learned here at CT to help racers race smarter. You story is proof of that concept and it is a lot of fun to succeed especially when you think back and know you worked hard and smart to get there.

Drive Shaft Angles

Bob,
We have been putting extra effort in to make sure the rear end is square, tail shaft is in alignment (straight) with the pinion, tire contact patches are inline, etc., but considerable discussion has centered around the angles of the pinion shaft and the tail shaft of the transmission being “equal and opposite”.

Does that mean if the pinion shaft is down 2 degrees, that the tail shaft of the transmission must be up 2 degrees; or if one is down 2 degrees, the other should be down the same amount? We have two super late models we run in Michigan and Wisconsin. Any comment would be deeply appreciated.

Thanks, Dave.

Dave,

Your questions are timely. I just went through this with a northeast modified team running on dirt. In their case, the tranny shaft was running downhill to the rear at six degrees and the pinion was down to the front about four degrees.

This driver asked me what he should do to make the alignment better. So, I suggested that he reduce the tranny angle and make the pinion equal and opposite to the drive shaft. This meant he had to run the pinion uphill to the front to accomplish having what the drive shaft experts say is critical alignment.

He did that and the results were very noticeable. A vibration or harmonic that he had felt ever since he had the car was now gone. The car had much better bite off the corners and he has won several races with the car since making the changes.

What the experts say is that when you have equal and the same angles, as the engine turns at a constant RPM, the pinion will accelerate and decelerate twice per revolution, speeding up and slowing down. In the race car, this would be like pushing and letting off the throttle multiple times while you are accelerating.

This cannot be good for bite, especially on dirt where grip is at a minimum. In order for the rear tires to rotate smoothly and at the same RPM through the entire rotation, the tranny and pinion must be equal and opposite angles to the driveshaft. And the actual angle does not need to be more than two or three degrees.

’69 Chevelle Setup

Bob,

I’m building a 1969 Chevelle street stock for Sandusky Speedway, a 1/2 mile asphalt track. Our minimum weight is 3,400 pounds and we must run a stock sway bar. My question is, what is a good starting point for front and rear spring rates?

Dave Barnes.

Dave,

I would love to be able to tell you what springs to run, but no one can do that without knowing a lot more about the car. The concept of total package means that we must make all of the systems on the car work together.

Just looking at the spring rates is not going to help you. You need to decide what works with your rear suspension, a leaf spring for this car I believe, verses what works for a metric four link. The two suspensions are vastly different and require much different spring rates.

The leaf spring rear suspensions have a very wide spring base and as such, require less overall spring rate than other types of rear suspension. These cars tend to be better on tight, high banked tracks once you get the right springs in the car.

What many times determines what rear spring rates you use, depends on how the front suspension is setup. You must consider your front end design including front moment center location, bump steer and Ackermann. Any of these that is not right can upset the entire setup and make choosing spring rates very confusing.

Piston Clearance Correction

Bob,

If you measure a block bore at 4.030” and the piston diameter at 4.028’, the clearance is 0.002” not 0.001” that you wrote in the Dec., 2014 Circle Track engine rebuild. Piston clearance is measured on one side of the piston not both sides like you stated.

To subtract piston from bore and divided by 2, I don’t think so. The old school way to measure piston to bore clearance is to use a 1/2 wide feeler gauge placed between the piston and bore tight enough to require about 8 lbs of pull to move it. This still works with uncoated pistons.

Bruce.

Bruce,

Thanks for pointing that out. The accepted definition of piston clearance is the difference between the bore diameter and the piston diameter. If you want to think about a centered piston and what the gap would be on both sides, you could divide the clearance by two.

So, for a piston clearance of 0.003”, the side clearance would be 0.0015”. Some old school guys will use two feeler gauges set on each side of the piston. In this case, each would be fifteen thousandths to get the 30 thousandths clearance.

Most engine builders do not recommend using feeler gauges to measure the piston clearance. You can use bore gauges and micrometers to measure for piston clearance and get a much more accurate answer.

Evening The Field

Hi Bob,
I am off and on Street stock racer with not much experience. My concern is having fun. So I am most interested in the articles about crate engines, i.e. evening the field. I sometimes think that too many rules can make it more complicated.

How much time and money is spent by the drivers and tech persons to police things? I see a broad range of rules in street stock ranging from requiring entirely stock parts to allowing after market springs and suspension parts as well as crate engines.
What do you think about using tire rules, limiting intake/carb and exhaust rules alone to even the field? Are smaller tires enough to make even the most extreme suspension modifications irrelevant? Could smaller carbs, intakes, and exhaust manifolds likewise make extreme engine modifications useless?

L. C.

LC,

Many sanctions and tracks now use weight and other differences to even the competition between teams that use different engine packages of varying power. Yes, it does work to an extent.

As I have pointed out, the use of smaller tires limits the advantages of more powerful engines, but nothing can limit the advantages of good suspension design and setup. That is the area where a team can excel and not need to spend lots of money on high horsepower engines.

Evening the field is a complicated and unfair thing in reality. Say a team does their homework and the suspension is just the way it is supposed to be and the setup is balanced to where they are using the four tires to maximum advantage, should they be penalized for being faster than the rest of the field?

If we can limit our “evening the field” to power and leave the setup improvements alone, then I am all for bringing the field closer to even. The goal in racing has always been to find the right setups that is fast and stays fast and having a driver who can use that performance to win races. That should never be legislated out of the sport.

The post Sealed Engines Revisited appeared first on Hot Rod Network.

The most significant leap in safety technology during the past 20 years has been the development and implementation of head-and-neck restraint systems. Looking back over the course of time, we find in retrospect a great number—maybe most—drivers who lost their lives in stock-car racing accidents died from “brain injury.” I use quotes around the word because it is a little misleading.

When I heard the term, “brain injury,” I always thought it meant the brain had been bruised or damaged in some way inside the skull. That may have occurred, but what actually kills lots of drivers who impact concrete walls—or other immoveable objects—is a little different. It is the violent forward motion of the unrestrained head when the car stops suddenly. Up to this point, we have done a good job of restraining the body of the driver with wraparound seats and five- and six-point belts, but what about the head?

I grew up in Daytona (a lucky coincidence) and used to regularly visit the track. I could always get the highest-level passes for whatever was going on out at the track. One day around 1965, I heard some more experienced NASCAR drivers talking to a few rookies about what to do in the event of a crash. The speeds then were approaching 180 mph, and these cars were very similar to the glorified strictly stock classers that now run at the local half-mile track.

The older drivers told the rookies when it was imminent that you were going head first into the wall, you should move forward into the belts and tuck your head down against the steering wheel. The point was, you’re going to go forward anyway, and it is best to be tight against the belt rather than fly forward and strike the belt.

The head, inside the helmet, when placed against the steering wheel created a restraint whereby the wheel absorbed the impact and restrained the head, much like the current breed of head-and-neck restraints. That, my friend, is why many stock-car drivers going 180mph, and upwards of 210mph later on, survived high impact crashes at Daytona. But we can do much better now.

One of the things I really like about my job is that I get to inform racers how to better enjoy this sport, and more so, how to survive it. Read on and take this information to heart. It is probably the most important thing you can learn in your entire career.

Some Crash Facts
We have previously researched the leading suppliers of head-and neck restraints and also the SFI to nail down the specifics about head-and neck injury dynamics. We wanted to know where the threshold lies between survivability and injury in relation to speed versus impact. Here is what we found.

In a typical race car, the driver’s body is restrained by the seatbelts and seat. This leaves the head free to move unrestrained in the event of an impact. This unrestrained movement can lead to injury, and in many cases, death. To combat this, head-and-neck restraints have been developed.

Recent racing history tells us there is a real and present danger to the driver associated with sudden deceleration when crashing into concrete walls or other objects at high speeds. In addition to the rash of top-level professional drivers’ deaths, which we are all aware of, there have been fatalities on the short tracks due to the very same conditions these products are designed to address.

The SFI certifies safety equipment for racing. According to sources, the threshold established for preventing serious injury to the head and neck begins at and above 4,000 newtons. One pound of force is equal to 4.4 N. This would be about 5 g’s on the entire body of someone who weighs 180 pounds. The SFI testing level is 70 g’s. For a force exerted on the base of the skull and neck that is equal to the weight of the head (including the helmet and so on) multiplied by 70. The head and neck cannot physically contain such a force if unprotected. The damage is similar to what happens when someone gets hanged, only worse.

The ultimate force necessary to cause injury in each person depends on varying factors and that make choosing a threshold difficult. The following are factors that enter into the complex circumstances of crash survival: 1. the driver’s age (the younger you are, the worse your chances, up to approximately 21years; 2. the driver’s weight, especially the head; 3. the physical fitness of the driver; 4. the driver’s gender (you pick which is better); and 5. past injuries that may increase the degree of injury in later events.

So choosing a threshold, such as 4,000 N, does not necessarily indicate a perfectly safe condition. It merely indicates you are much better off if a device can lower the force on your head and neck to something below that threshold level.

Without Results
Without an H&N device, the forces on the head and neck can exceed 35 g’s in a 60-mph crash. The SFI test level force of 70 g’s is probably much higher than we will ever experience, but it is possible. The various safety devices tested must lower the force felt at the base of the skull to well below the 4,000 N level (909 pounds of force).

What exactly does that mean? It is all dependent on the amount of head weight, plus helmet weight. We found this interesting quote on the SFI website: “An adult human cadaver head cut off around vertebra C3, with no hair, weighs somewhere between 4.5 and 5 kilograms, constituting around 8 percent of the whole body mass.” In our 180-pound example, the head would weigh about 15 pounds. A helmet weighs about 3 1⁄2 pounds. If we divide 909 pounds of force (4,000 N) by 18.5, that equals 50 g’s.

This may indicate a 180-pound person will not survive a crash that exceeds 50 g’s, according to the 4,000 N limit. In reality, the actual force of a sudden impact may far exceed 4,000 N because of the whipping effect as the head is thrown forward on impact. So, a 35g crash, measured in the car, may instantaneously exert more force than that on the head and neck, hence the 70g test level.

A heavier head and helmet combination necessitates experiencing even lower g-force in a crash in order to survive. We can see where g-force and newton numbers are subjective. The bottom line: We need to reduce the loads on our head and neck in order to survive a crash. Head-and-neck restraint systems do just that. Racing without one is like walking on a tight rope with a noose around your neck. If you fall off, well, you die.

Several companies have addressed this safety issue and developed products that reduce the risk of serious injury in a frontal and near frontal crash. If you don’t have or don’t use a head-and-neck restraint system, it’s time you consider purchasing one before you actually need one. Let’s take a look at what’s out there. Note: The descriptions are copied from the websites of the manufacturers.

HANS Device
Jim Downing and Bob Hubbard started making and selling HANS Devices in 1990 before the broader racing community really understood much about the biomechanics and significance of head-and-neck injuries. In 1997, they started developing the current version. These new devices are smaller and lighter and fit a broad spectrum of racers and cockpits.

“The HANS III represents the third generation of injection-molded HANS devices and features a contemporary approach to reducing weight. Using an all new design and polymer, the device features a hollow collar that substantially minimizes weight. Engineered reinforcements ensure an exceptionally strong structure that provides the same level of safety as every HANS device. The reduced mass guarantees the lightest and most comfortable injection molded HANS ever.”

Impact Accel
“New in 2015, the Impact Accel offers unparalleled comfort combined with the ultimate in frontal and angular impact protection. Affordably priced and adjustable, the Impact Accel is your go-to safety device regardless of seat angle or complement of motorsports. Constructed from lightweight yet durable DuPont carbon composite material, the Accel can withstand the rigors of nightly racing whether you compete in drag, circle-track, or off-road. Includes helmet hardware, no need to purchase separate FHR posts for your helmet!

“Features: Manufacturer certified to comply with the SFI Foundation’s 38.1 specification, adjusts between 10 to 40 degrees for a variety of uses, weighs less than 2 pounds (1.8 pounds or 816.5 grams), body forming shoulder pads offer unparalleled comfort, offers superior angular impact protection and SFI 38.1 compliant, made from carbon-fiber DuPont® composite materials, includes helmet hardware, no need to purchase separate FHR posts for your helmet.”

Leatt Brace
“Unique combination of premium comfort and outstanding protection. The new MRX Pro has improved SFI 38:1 test results due to the improved polymer chassis material, flexible frame design for a greatly improved fit and comfort with optimum control of neck-force reduction and head deceleration, New, increased collarbone relief area for improved fit and comfort, fire-retardant Nomex washable padding for vastly improved strapped‐in comfort and reduced harshness of helmet to brace impact, new MRX Pro foam collar included for fatigue reduction, single rear collar angle design for perfect fit and function with all seat angles and driver positions, seatbelt channel, guiding the belt away from the soft tissues of the neck, Kevlar fire-retardant tethers for frontal and side impact protection, optimized tether length for great head movement and maximum protection. Kevlar tethers that stretch only 2 to 4 percent, sliding tether for improved field of vision, head movement, and driver comfort, fits over or under 2 and 3-inch seatbelts and helmets with HANS-type anchor posts, anchor post kit and anchor post nut wrench included, SFI 38.1 tested and approved for optimum protection.”

NecksGen REV
“Low profile, lightweight carbon composite structure, stainless steel hardware and buckles, belt channels fit 2- or 3-inch belts, winglets keep belts in place, Kevlar tether, replaceable Nomex padding, full range of head motion and lightweight.”

Schroth SHR FLEX
SFI 38.1 certified, high strength carbon reinforced materials, angle independent low collar design, dynamic articulating collar, rate responsive bumpstop, sliding “twist anchor” tether system, SlipStop belt retention system, integrated shoulder padding system, form fitting lower legs.”

Simpson Hybrid Series
“Simpson’s Hybrid Series is designed for easily exiting the car without the danger of being entangled in other gear. Simpson head-and-neck restraints offer the lowest profile of any comparable device. Plus, they provide you with maximum comfort and maneuverability.”

Z-Tech Sports Series
“The new series 1A has new features never seen before in the head-and-neck restraint market. These new patent-pending features include:

Advanced Axis Adjustment adjusts width, arm angle, and arm width allowing different body shapes and sizes. Also can be adjusted to different race vehicles, glass reinforced nylon is a lightweight and very specialized material that offers leading structural characteristics, stainless steel hardware screws and binary post built with high quality and strength gives long lasting strength, Kevlar webbing tether connects helmet to restraint, Spring Clip Quick Connect allows easy connection and removal from helmet with one hand, belt channel with wings accepts 2- or 3-inch belts, replaceable padding washable and replaceable padding gives ease to clean or replace for continued comfort, helmet hardware all hardware needed to connect included, SFI 38.1 certified.”

Safe Drivers First
No matter if you’re racing Street Stocks on dirt, Legends cars, Pro-4 Modifieds, on up to Super Late Models, or any other short-track car, you need to protect yourself from a high g-force frontal impact. These head-and-neck restraint systems are specifically designed to help you survive those impacts.

It may seem like a rare occurrence to many, but it only takes one crash to hurt you. Do the right thing by completing your safety package with a head-and neck restraint system. Now, more than ever, there are many to choose from and the prices are lower than ever.

Sources:

Hans Performance Products
(888) 654-7223
www.hansdevice.com

Impact Race Products
(317) 852-3067
www.impactraceproducts.com

Leatt
(800) 691-3314
www.leatt.com

NecksGen
(619) 328-0410
www.necksgen.com

Scroth Racing
(800) 884-2358
www.scrothracing.com

Simpson Racing
(800) 654-7223
www.simpsonraceproducts.com

Z-Tech Sports
www.z-techsports.com

The post Head-and-Neck Restraint Systems appeared first on Hot Rod Network.

Racers who have been in this sport long enough have seen situations where one or two teams dominate the racing at a particular track. Typically, the only people who are happy about it are the winning crewmembers. Things can—and do—get ugly.

The other racers grow upset because they’ve been pouring tons of hard work and money into their programs. Yet, the dominant team still rockets off into the wild blue yonder and makes them look like chumps.

The officials have to listen to the whining remainder teams arguing that the dominant team is cheating. They must be, right? So, the dominant car receives an inordinate amount of attention in the tech line and after the race. Everyone wants to know why that car is so fast compared to the other competitors.

In most rulebooks, the allowable setup parameters are simple: 1. four springs and their associated spring rates; 2. four shocks with various rules about spending limits; 3. a weight limit and unlimited weight distribution possibilities; and 4. geometry considerations for a changeable front and rear suspension. Oh, I add number five, align your car any way you see fit.

It is as simple as that. Consistently winning cars have found the perfect combination of those five elements for the class and the track they are running. Cars that dominate competing in traveling series have found a better combination to accommodate the different tracks, usually by running them many times.

…when you find that magic setup that kicks butt, maintain it. Don’t make big changes looking for more when the odds are that there isn’t much more to be had. There’s only less.

I have had the privilege of working with several dominant teams during my career. Several stories stand out, so please indulge me. Right after I decided to become a consultant, a team asked if I was available to help out, and needing the money at the time, I agreed. That is how I became a paid consultant, and it was a career changing decision for me.

This team was running at a track that participated in the NASCAR Weekly Racing Series, which boasted 200 racetrack members and a national point’s system. Our team was leading those points as of July 1996. The number 98 Late Model stock car team driven by Wes Troup won 13 out of 19 races. Later in the season, the attention paid to that car came to a head.

After yet another win, the tech officials, including many people who had come in from other regional tracks, tore the car apart. Nothing was left on the frame but the roof panel. Everything was gutted and the search was on for traction control. None was found. The secret everyone was looking for was a perfectly put together package that stayed fast longer than the other cars. It was as simple as that.

Fast forward to 2015 when the Dick Anderson owned and prepared CT Project Modified took to the track. It has now won 13 races in a row at several tracks and has gone through the same teardown that Wes experienced way back in ’96.

The secret to Dick’s success is twofold. He knows how to setup a race car and he knows how to maintain that setup. You see, many of us discover that perfect combination of things that allow us to win. But few of us can maintain that winning streak for any length of time. As a result, dominant cars usually only have limited runs.

After Wes’s dominant 1996 season, his wins trailed off and in 1998 he was unable to put together even one win during the first half of the season. I married the love of my life, Karen in May and we took a honeymoon trip up through the North Carolina mountains, through Virginia, and ended up at Old Dominion Speedway to see my friend Wes race.

Visiting his pit in the early afternoon and asked him about the problem. According to him, they’d been experimenting, but could not find the right combination. I asked him to bring out his notebook for the 1996 season and and showed me notes on the old winning setup. “Put that back in the car, I told him. “It’s the same racetrack, the same tires, and the same car.”

He did. And sure enough, he won that night. It’s not about how smart anyone is, it’s about finding that magic setup that kicks butt and maintaining it. Don’t make big changes looking for more when there probably isn’t much more to be had. There’s usually only less.

As for the tech officials and other racers, often it’s not magic going on, and no, the dominant car is not cheating. Wes and Dick were not cheating, which was proven by a thorough tech inspection. You can’t prevent a dominant team from “stinking up the show,” as some promoters have put it.

The fans love a winner, to a point. Appreciate the hard-working teams. Yes, it can get boring to have the same team win over and over. Why don’t the promoters mix it up? Change the rules; if a car wins two in a row have them start at the back at the next race no matter where they qualify. Some tracks offer a bonus to cars that start at the back after winning several races. A fast car coming from the rear and making its way through the field is very exciting and the fans love it.

The worst thing a track can do is dumb down the tech and take away innovation, basically outlawing the fast cars. Allow the teams work on their cars, within certain boundaries, and reward hard and smart workers. It’s what built America, right?

If you have comments or questions about this or anything racing related, send them to my email address: MPanure@enthusiastnetwork.com, or mail can be sent to Circle Track, Senior Tech Editor, 1733 Alton Pkwy., Ste. 100, Irvine, CA.

Bump Steer With Wheels Turned

Hi Bob,
When racing on dirt, and in the corner, if my steering is turned, let’s say, 10 degrees to the right? If this is the supposed to be the most important handling part of the track, why advise us to check bump steer in the straight-ahead position? Who cares what happens on the straightaway? The center link, tie rod ends, and spindles arms are not in the same positions and wouldn’t seem to take the same arc.

 – JK

JK,
You are correct. We advise you to check your bump steer with the wheels turned the same as you turn them through the turns. In your case, you turn the wheels to the right, and that is where you should check your bump.

It doesn’t hurt to check bump in straight ahead, as well as turned positions. These tests may indicate a serious problem with some components if the bump is off significantly when the wheels are straight as opposed to turned.

Rear Metric Moment Center
A past article in Circle Track showed a diagram of how to determine rear moment center height for a metric four-link car. It states this rear moment center is unusually high. Other articles have indicted that the closer you get the moment center to the center of gravity the less roll there is. Is this right? Is that why we want a soft spring in the RR and a lot of rear spring split in our asphalt metric Stock Car, to get it to roll? Would it be helpful or harmful to decrease the angle on the upper rear control arms to lower the moment center height?

Thank you,
 – John

John,
You answered the question. Yes, less angle in the upper links on a metric rear suspension lowers the rear moment center, causing the rear to want to roll more. The problem with the stiff rear suspension is the front wants to roll more, which makes the car out of balance dynamically.

Running the softer, right rear spring rate helps the rear to want to roll more, which helps balance the setup. By lowering the rear moment center, you make the rear suspension more compliant, or softer, thereby causing more roll angle to match the front.

Bob,
We have been putting extra effort in to make sure the rear end is square, the tail shaft is in alignment (straight from a tip view) with the pinion, the tire contact patches are in line, etc. However, we’ve had considerable discussion about the angles of the pinion shaft and the tail shaft of the transmission being “equal and opposite.”

Does that mean if the pinion shaft is down 2 degrees, that the tail shaft of the transmission must be up 2 degrees, or if one is down 2 degrees, the other should be down the same amount? Any comment would be deeply appreciated.

 – Dave

Dave,
According to the driveline experts, for proper harmonics and driveline geometry, the tail shaft and the pinion shaft must be parallel. So, if the tail shaft is pointed down towards the rear, the pinion must be pointed up the same number of degrees.

If the tail shaft is pointed up, you must point the pinion down. Most setup information always advises us to angle the pinion down a few degrees for more bite. I’m not sure where this came from, but in a recent case with a NE modified, when we ran the pinion up in relation to a tail shaft pointed down, the car gained bite and removed a persistent car vibration.

Bob,
Thank you for your insight regarding moment centers. We are currently racing an asphalt Modified with stock lower A-arms, a Camaro type tube front clip, and a straight rail on the right side. But we have a problem in the rear, with a short 22-inch long J-bar.

I want to move it below the rear end centerline by 3 to 4 inches, but my brother, who’s the car owner, won’t take it past 1-inch below. Do I give up or not? It’s regularly a Third place car. I’d like to be better. Any help is greatly appreciated.

 – Unsigned

Unsigned,
Normal rear axle tubes are centered about 13 inches off the ground. This is based on an 86-inch tire with a radius of 13.68 inches and a tire squash of a little over a half inch. You are running a J-bar at around 12 inches off the ground and want to try running it 9 to 10 inches off the ground?

Lowering the bar would have a tightening affect on the car. Moving it 2 to 3 inches would be a very big move. Usually, if we thought the car was loose, we would initially move the bar in 1/- inch increments until the car felt good, then move it up or down in 1/4 inch increments to fine tune the setup.

Perhaps you should convince your brother to try much smaller changes and see if the car gets better or worse. The proper J-bar height directly relates to the rear spring rates and the spring split rate from side to side.

Generally, the stiffer the rear springs, the lower we run the bar, and the more spring split we run (right side stiffer), the lower we can run the bar. With softer spring rates and less spring split, run a higher bar.

Bob,
This may be a little off the beaten path, but I have a Street Stock that was hit fairly hard on the right front, and subsequently, expertly repaired. However, now when I weight-balance the chassis on four-wheel scales, it takes a significant amount of wedge adjustment on the right front just to achieve good balance.

I can’t seem to get a handle on which way to go with my A-arm mounts to reduce this wedge. Do I raise the lower right mounts or lower the upper right mounts? There’s no obvious visible damage. Can you point me in the right direction here? And since I’m supposed to know what I’m doing, please withhold my name.

– Withheld

Dear Withheld,
What has probably happened is the frame is bent and the right front part of the clip is higher than before. Therefore, you need to input more jacking screw than you were accustomed to before the crash to get the same cross-weight percent.

The only good way to fix this it is have the frame straightened at a frame shop. To check your front clip, level out the rear of the car and measure from the floor to the left and right lower control arm mounting bolts. They should be the same.

If not, note how much difference there is and relay that information to the frame shop to see if they can twist it back into position. If you leave the car the way it is, you have different control arm angles relative to the other side of the car, which upsets the front-end geometry. It would be extremely hard to reposition the right side control arm mounting locations the way you suggested.

The post When Race Teams Dominate appeared first on Hot Rod Network.

It was announced today (7/15/16) in a story by sports writer Godwin Kelly in the Daytona New-Journal that Dale Earnhardt Jr. will sit out the next Sprint Cup race at New Hampshire because of the lingering effects of several concussions he has had. In the October, 2012 issue of CT, we posted a full report on a fellow racer who suffered his own battle with repeated concussions.

Now would be a good time to review some of the information we presented then. This kind of information never becomes obsolete, but we continue to learn more and more about this dilemma. I can say that the subject has improved dramatically and is now participating again in short track racing as a car owner and crew chief, but will never drive again.

Lack of knowledge is common for some forms of injury because of the similarities of symptoms to other illnesses and because the injury itself is not so common among the general population. Dale Jr. thought he had either allergies or a sinus infection and sought medical help for those. Instead, after being examined by a specialist, his symptoms were found to be related to his past concussions.

You are reading this because you either are a race car driver or know one. Our original subject racer had a long and very successful career and began racing back in 1976. Jeff Vochaska had won 116 races and numerous track championships over the years up until he himself began having symptoms similar to Dale, Jr. It was an accumulation of mild and not so mild concussions that led to a condition that had left him unable to function normally.

I did a series of recorded interviews with Jeff over a week long period of time and here is some of what I learned. I include quotes from Jeff as well as information from experts. Take this information to heart and we hope some of you who need it will learn from it.

In my interview with Jeff I asked, looking back, and knowing what you know now, how long ago did you first remember having the symptoms of concussions with your racing? “About fifteen years ago I started having the concussion problems but I didn’t know what they were.”

After talking with Jeff, I read up on concussions and found that a class three concussion is when you hit your head and see stars. In the case of Junior Seau, the famous football player who committed suicide, he had probably experienced five of those events per game on average.

A class one concussion is when you are rendered unconscious. A class two is somewhere in between. Jeff told me, “Yea, I’m saying that I guess that I probably had between 60 and 70.” I asked him, what do you think caused the concussions, was it the head hitting the roll bars and the steering wheel? His answer, “Usually, yea, it was my head hitting the roll bar, but towards the end, I had so much safety equipment that I think a lot of times it was the sudden stop and it was just my brain hitting the inside of the skull.”

The last ten years of his career, Jeff had the best of everything money could buy for safety equipment. He had the head and neck restraint, full wrap around seats, light weight helmet, etc. and that didn’t seem to stop the concussions. What that leads me to believe is that past a certain point, no amount of gear will offer protection when you have accumulated a certain amount of injury to your brain and surrounding tissue.

He started having these sleepy days and he’d start calling in sick to work and the doctors weren’t able to pinpoint what was wrong with him. “I feel like I had the flu all of the time, except I had no fever. Your sick to your stomach and you have a headache. That’s how these concussions feel.”

“Early on, you don’t really notice the concussions, but one of the early signs that they are affecting you, if I took a hard hit on Friday or Saturday night and I was feeling sick, I would sleep all day Sunday, Sunday night and all day Monday. That was one of the early signs.”

“Then they started lasting longer. Originally it was only two or three days, but then it got to the point where I would be sick for a couple of weeks. I then finally got to the point a couple of years ago where the symptoms just never went away.”

PSC (Post-Concussion Syndrome) is a set of conditions that occurs after a concussion and CTE (Chronic Traumatic Encephalopathy) is the result of multiple concussions and other forms of head injury. Both can last for weeks or months, and in extreme cases, for years as in Jeff’s case.

There is no known treatment for either syndrome. There is treatment for the symptoms of the conditions. Some people eventually get better and some do not. The only prevention is to quit having concussions before the more difficult symptoms appear. Once a certain threshold is reached, there may be no turning back.

We hope that through this interview and the presentation of this information, we have educated you to these dangers. This is not meant to say that CTE is a common problem or that everyone who drives will experience the symptoms we mentioned.

What this does say is be aware of the possibilities and be on the lookout for the early indicators of concussion problems not only for yourself, but for others around you. It is your job to educate your doctors to recognize the symptoms of concussion and to help them make appropriate diagnosis and recommendations, including forbidding future driving of race cars.

The post What Racers Should Learn from Dale Earnhardt Jr.’s Concussion Condition appeared first on Hot Rod Network.

After William Ray sold the family business last year, he decided it might be a good idea to get into the racing promotion business. He chose a track that has been close to his heart since he was a child. Citrus County Speedway, located an hour north of Tampa, FL, was a place he remembers coming to when he was small and where he himself raced on and off for some twenty years.

He is not the first racer turned promoter, and he won’t be the last, but he is the newest one. This was something he wanted to do to be able to spend more time with his nineteen year old son Cameron, as well as to provide a benefit to the community that he has been a part of for so long.

The facility is a part of the Citrus County Fair Grounds and as such is leased to operate as a speedway. The Fair committee almost didn’t re-lease it when the former promoter walked away about eight months ago. It was their knowledge and trust of the Ray family that caused them to re-think how the land would best be used.

William went into this project with total commitment. Every cent he invests in the speedway becomes the property of the Fair Grounds, so it has to produce, not just to make a profit, but to pay back the initial investment. A lot is at stake.

A complete remake supervised by this father and son team has been underway since the first of the year. From front to back, just about everything is new or re-furbished. The pits are now completely paved with concrete pads for the teams to park their cars on. The track has been ground and re-paved into a very smooth and perfectly shaped surface. It will take a few races to get it “run in,” but it’ll be fun for the competitors meanwhile.

The track has a figure “8” X included in the design that William has seal coated and will be used for kart races and exhibitions by monster trucks, etc. The grandstand seating is “new” having been a part of the backstretch stands at Daytona. They were removed last year as a part of that speedway’s giant renovations and William got a deal.

The seats were fitted to the existing supporting structure and look great. All of the walkways are made of brick pavers which are pervious, cool and eco friendly. That is, when it rains, the water soaks into the ground beneath the pavers.

The three story scoring and announcers tower sits atop the concession area and all of the equipment for cooking and preparations of the food and drinks is all new. Nothing was spared in William’s vision for this track.

Above turn four sits more grandstands and an adult outdoor bar where you can sip your beverage while watching the races. And that won’t be very far off by the way. As of this writing, the opening day is only two weeks away scheduled for July 30th.

When promoters have themselves been racers, they know things and feel things that persons who have only been on one side of the game cannot know. One of those things is that the racer is the key to making a racing facility work. If you can make the racers happy and comfortable, not only will they will come, the fans will too.

At CCS, all of the purses are guaranteed and the payout window is located in the concession stand area so that the fans will have a chance to mingle with the drivers and teams after the races. The connection between those two groups is the key to keeping everyone coming back week after week.

The safety crew will be “rented” and consists of a professional team that has operated at race events and knows how to handle any situation that might come up. We have often pointed out the lack of professionalism at certain race tracks across the country and were pleased that William and Cameron decided to bring in this team.

William has tailored the rules so that teams from other areas of Florida can come to CCS and not have to change their cars around to fit the rules. For example, some tracks have the Modifieds, a fast growing class in circle track racing, running slicks whereas CCS Modifieds will run treaded tires. The CCS rules will allow both the slicks and the treaded tires.

There is a slight difference in performance, so they might add a few pounds to the “slicks” cars to equal out the gains those tires produce. But at least those other teams won’t have to restock their tire inventory with different tires than they usually run. That is the kind of forward thinking that helps the racers and makes them appreciate the promoter.

As the head of the tech squad, Bob Wise, a long time ARCA official, will oversee all of the rules enforcement at CCS. Bob comes with a wealth of knowledge and will be highly respected by the teams competing here. Fair and equal officiating is one of the keys of success as racer turned promoter William Ray knows all too well.

And wouldn’t it be great if the race tracks in Florida could do what those in Wisconsin and the Northeast do and run their schedules on non-conflicting days, like Wednesday, Friday, Saturday and Sundays? And with the low price of fan admission, only $5 at the gate at CCS, a family could afford to take in several races a week.

If you live in and around the Tampa, Ocala or Orlando area, come out and see for yourself what a fine facility this has become. CCS is located in Inverness, FL, about 60 miles from either Tampa or Orlando and about 30 miles from Ocala. The races are scheduled to be run on Saturday nights, but William and Cameron are still making plans for the 2017 schedule and they might shake things up a bit, who knows.

Our Project Modified driven by Josh Todd and owned and operated by Dick Anderson will be there for this historic first race. They have won five races so far this year and you might want to come out to see if anyone can knock them off their pedestal.

The post The Rebirth of Citrus County Speedway appeared first on Hot Rod Network.

When we think of racing safety, we almost always think of the driver and what the team can do to protect its driver. But the safety team at your track plays a huge role in determining if you will survive an event. Here are a few important things to consider concerning racetrack safety.

During 2014, a professional racetrack firefighter at Kalamazoo Speedway, Jake Steele, and I wrote an article about safety crews. The information we passed on then bears repeating, along with a few additions.

I was very fortunate to have had the opportunity to travel to tracks all over the country from 2010 to 2014. As a result, I saw a great many and varied kinds of safety crews. Not all of them were outstanding. Most of the crews were staffed by professional safety personnel who do rescue work as a day job. Based on my observations and information from Steele, here are some ideas on how to make your track safer.

Who Does What

Your safety crew should all know their roles for each situation that might come along. That includes, who goes to the drivers aid, who takes care of the track cleanup, who watches for and controls traffic, and who calls for EMT back up.

A very serious accident can cause a lot of confusion. Everyone wants to help out with the victim, but that is the wrong approach. The safety crew must have assigned duties and follow the plan in order for everyone to be safe, first off, and the rescue plan goes smoothly.

Carry the Proper Equipment

The KTS crew has two trucks that carry an aircraft foam suppression system, the Jaws of Life to cut out drivers who are trapped, four brooms, an oil dry spreader, three different kinds of fire extinguishers, a sawzall, drills, and a complete first-aid medical kit.

What you should carry for your crew is your choice. Different tracks might require different equipment, so examine your needs and plan out which tools might be needed for any situation. As the only safety crew on the property and might be called on to assist a spectator or even crew members in the pits, as well as the drivers.

Know Your Tools

Your crew should know how every tool on the truck works and all of it should be checked at the beginning of each race day. For experienced fire-fighting personnel, the training has already been done, but most crews have additional, inexperienced helpers who can assist with extraction, fire suppression, driver removal, and more.

Take the time to go over each and every piece of equipment with members of your crew who may not be as familiar with the equipment as you are. I have seen volunteer fire fighters forget how to turn on the fire hose and waste precious minutes doing so.

Driver Education

Every driver who races at your track should know what you require from them. Explain your needs to them in the drivers’ meeting. Encourage questions and be sure everyone is on the same page.

Discuss anything you can think of that the drivers need to know at a separate meeting held for each class that runs. That way, the numbers are smaller and you can concentrate on each driver in the group. Plus, the information provided from class to class might necessarily be different. You probably know certain drivers who need more education than others, as well.

Be Geared Up

The safety crew must always be geared up and ready when cars move onto the track. It doesn’t matter if it’s practice, qualifying, or the feature. Don your helmet, radio, gloves, fire suit, Nomex hood, boots, and eye wear.

During the heat of the summer, many crews are reluctant to wear the heavy suits, but how much time does it take to get all of that on? In a fire where the fuel tank has ruptured, there is very little time to act, so be ready.

Race Control or Flagman

Whoever is in control of the cars on-track should always get the safety crew’s approval before turning the cars loose. In reference to the last item, the fire crew should remove those heavy coats and pants to cool off between on-track activities and might need a few minutes to get them back on.

If the control center thinks ahead, they can alert the safety crew that cars will be on the track in X minutes and ask the crew to let them know when they are ready. This keeps everyone on the same page and assures that everyone will be ready to go.

Hand Signals

Each safety crew probably has several hand signs that can tell the drivers where to go, how to avoid oil or other hazards, when to scuff the ready-dry, when to get high or go low on the track, and more.

If a hands down motion means stop immediately and the driver does not know that, someone could get hurt just from the driver not being able to see a hazard. You can refine those signals with the drivers, and they may have opinions as to what is better for different situations.

A race car windshield that has been sprayed with oil during a race is difficult to see out of and if the lights are just right, the glare could further impede their vision. The track crew has to be aware the driver just might not be able to see in all directions and act accordingly.

Roll Over Procedures

In the event of a rollover, the driver must stay buckled in until the safety crew arrives to assist, if there is no fire. If no one is injured, the standard procedure is to roll them over while they are in car and buckled up by using the NASCAR technique.

This involves rolling the car up on its side preferably with the driver side towards the ground, attaching a wrecker cable to the underside, and lowering it slowly to the ground with the wheels down. That way, the driver does not get whiplash, the suspension suffers less damage, and no one gets hurt from the sudden fall.

Local EMS Assistance

Plan ahead to have your local EMS (emergency medical services) on standby. They should know when and how you want them to work with you if the need arises. It is great if the radio communications are coordinated, too.

When a driver, or anyone else at the track is seriously injured, you are required to seek professional medical assistance and transportation for the patient. This could include calling for a life-flight helicopter. If you don’t know how to do that, ask your local emergency provider and familiarize yourself with the procedure. It’s too late when someone needs to be transported stat from the track.

Many tracks are very far from the nearest hospital. When we attended Atomic Motor Raceway, we were about an hour away from any medical facility, and in the event of a serious injury, a helicopter would have been a must. Your track may be in a similar situation.

Never Get Out of Your Car

Well, almost never. Drivers should never get out of their car after it has been disabled on the track, unless it’s on fire or the track personnel tell them to do so. And don’t unbuckle your belts or take off your helmet until you are absolutely sure the other cars have slowed down for a couple of laps.

The racetracks need to incorporate this item in their rules, and enforce serious penalties with zero tolerance for breaking that rule. Getting out of the car and confronting another driver on the track is very dangerous and unnecessary. There’s always time back in the pits to talk things over.

Throwing the Red Flag

The flagman should know when you want a red flag thrown without asking. Any hard hit, rollover, or fire requires an automatic red flag without the safety crew having to ask. If the trucks are rolling to a serious event, they are concerned with avoiding other personnel, avoiding the race cars still on the track, and positioning themselves where they can do the most good.

Have a plan before hand for the flagman to wave the red flag if it appears immediate and quick response is needed by the safety crew. It never hurts to stop the race cars on the track. And the drivers must know to stop as quickly as possible where they are and pull to the inside of the track.

This red flag situation also applies if there is a need for medical attention to people in the pits or the grandstands during a race. The flagman should first wave a yellow, followed by a red flag, so the safety crew can turn their attention to the other situation and away from the race.

Race Car Safety

Every car should have a fuel check valve in the event of rollover. The safety crew or the tech crew must check this item on a regular basis. The car should also be equipped with a main power supply cutoff switch.

Most rules state that the cutoff switch be located within easy reach of the driver and outside personnel on either side of the car. That way, if the car is lying up against the wall with the driver’s side blocked, the safety crew can still reach in and cut off the power supply if the driver is unable to do that.

The drivers should all wear well-maintained neck restraints and other gear. Seat belts, drivers’ suits, gloves, and shoes must all be in good shape and function as intended. These items are not for show. Your track’s safety crew should mingle with the crews before the cars are scheduled to go onto the track to talk about safety and inquire about how each car is equipped.

This also gives the crew a chance to get to know the drivers and talk about any concerns. Some drivers might have special needs or disabilities that the safety crew would need to know about.

How the Track Is Constructed

How a racetrack is built and its layout might endanger race drivers. For instance, openings in the track might present a danger to cars by providing the opportunity for a head-on frontal impact.

If your track has openings at the entry or exit of the turns, imagine a car blowing a tire or getting bumped at speed and going into the corner of the opening so that the car stops immediately. It has happened in the past.

These openings must be cushioned with large tires, barrels of water, or other softening material that would mitigate a head-on collision. If the track is laid out this way, and there is no other way to get cars on and off the track, the layout might have to remain. However, there are ways to improve the chances for survival. Talk with your track management about those situations.

Safety Crew Suggestions

When working with sprint cars, the most important thing safety crews have learned is, if you are on the track and the cars are still coming around, stand perfectly still, and they will miss you. The second you move, you increase your chances of getting hit.

Always know what fuels the cars are running, so you can take different precautions. The safety requirements are different for a car running alcohol than for a car running regular gas. Depending on the fuel, you might not be able to see an alcohol fire. Look what the telltale signs are to identify those kinds of fires.

Install plenty of lights on your safety trucks at different angles, so the drivers can see no matter which way you park your truck. It is a good idea to carry yellow flags so the helpers can stand up-traffic, alert cars to your position, and to make sure they slow down.

Every track has unique needs when it comes to safety. It is best if the crew has members who are trained and experienced professional safety personnel. They can be local full-time or volunteer firefighters or EMTs. The more trained members on your crew, the better the care that can be provided when necessary.

Many of these types of people would jump at the chance to be a part of the races and use their skills to enhance the safety at the local track. Send a track representative to local fire stations to recruit members for their track safety crew. These personnel may also review the track’s safety procedures and equipment to recommend changes.

Finally, Jake told us that the most important motto is: “You cannot help a victim if you become a victim.” Track safety applies equally to the drivers, crews, spectators, and the safety crew. Your whole program will be enhanced when you provide a properly equipped and trained safety crew that works together with the track management and race teams.

The post Track Safety Crew Tech appeared first on Hot Rod Network.

I believe races and championships are won on the basis of having a strong philosophical approach, which is defined as being sensibly calm or rational. How you see yourselves as a team, and how well you maintain your confidence level will have a huge affect on the outcome of the season. You either must keep your strengths or get even better.

For the rest of the season, maintain at least what you have been doing that has gotten you where you are. But there are two ways this can go from here on out, backward or forward. Here’s how to avoid the pitfalls that will send you down the points list and a few tips on how to push for points and move up.

Preparation

I’m sure by now you have developed a week-to-week routine to prepare the car for the next race. Don’t make wholesale changes to that process. What you can do is add to the list of things to go over.

The parts of the car that you expect to last a full season might not be able to do so, for whatever reason. Events that occur during previous races might have compromised certain parts, like the clutch or a battery that is ready to fail. What can go wrong has a likelihood of going wrong at the worst possible moment.

The Driver

There will be a lot of pressure on you as the driver to maintain or improve in the points. Use your head. You now need to think more about the big picture. Mistakes that cause incidents and put you to the rear of the race will hurt you more than backing off and momentarily keeping your position.

The goals are to first finish the race, and then try to move up when, and only when, the opportunity presents itself. During a 35-lap race where you are running third, if you wait till the last 10 laps to charge, you’ll have better tires than if you tried and failed repeatedly throughout the race.

Patience is the key to getting by. When you hound the driver in front, you push him to be faster and more precise. If you backed off a car length or two, he (meaning he or she) will relax somewhat, and when you do charge up, you might just catch him sleeping.

The Crew Chief

As the leader of the team, your job is to keep everything organized and make sure the others are concentrating on their individual duties and not looking outside. When things get really competitive, the most focused team will perform better. It’s all about not making mistakes.

Reassure the driver that the team has his back. Help him maintain his confidence level, and teach him how to think out the race. Make him understand that a third- or second-place finish is better than spinning out and finishing fifteenth.

Testing

Late-season testing is all right as far as it goes. We are not trying any radically new setup ideas at this point, I hope. What you can do is try small, one-at-a-time, changes to see if you can tweak your performance to improve not only speed, but longevity.

For example, if you have been fast at the start of the previous races, but lose ground late in the run, your balance might not be perfect. The car might be a tick tight, but still turning well early on. If you were to raise the panhard bar a 1/4 inch, it might be all it needs to be more neutral and better on long runs.

Race-Day Practice

If you know your setup will be good come race time, don’t try to adjust to the heat of the day. Run your practice for the purpose of shaking the car down. Make sure the brakes are working well and the movement of the corners of the car feel normal. Put enough runs on the car to be comfortable that is has not changed for whatever reason.

Running less practice and purposely not working on the car sends a message to your competition that you are fully prepared and happy with the car. This tends to worry the other teams and might just cause them to scramble and make unnecessary changes to their car that will make them slower. We used to park the car during the last practice session.

Qualifying Better

Look back on your qualifying success, or lack thereof. If you are trying hard to qualify well, you might be overdoing it. It sounds backward, but it has been proven that overdriving the car will make it slower.

When qualifying on new tires that will be the most grip and the fastest those tires will go during their entire life cycle. Get the most out of them. Let them do the work. You really don’t need to do anything different than you did in practice except allow the car to roll through mid-turn at the quicker speed.

You might lift a little early, use less braking, and get into the throttle sooner with the new tires knowing they will grip harder and allow more throttle without spinning the tires. The added entry speed from less braking and the added mid-turn speed from the new tire grip will be enough to put you at the top of the charts.

Running the Race

Here is the hard part. Two things need to happen. Your driver needs to be aggressive, and he needs to be careful. Those two can work together, I know, because I’ve seen it happen many times. Controlled aggression is what it is called.

Yes, you need to finish as high as you can, and yes, you cannot get caught up in an incident. A DNF or bad finish could end your run for higher points. Don’t be that team that loses it at the end. Have patience. The spotter has a lot to do with how the driver runs his race. So, between the driver, crew chief, and spotter, make a plan and stick to it.

Tech Afterwards

Let’s assume you have run well, finished high, and now have to go through tech. I hope you have left room for chassis sag when you set your ride heights. Now is not the time to test the patience of the tech officials.

During late season battles, the tech crew is also performing at a higher level of competition, so to speak. They may just tech items they never teched throughout the year. Don’t get complacent with your weights, spoiler heights, and so on. Many teams push the limits of tech and end up losing out. That is what the tech officials are looking for, so be careful.

When It Is Over

The season will be what it will be. If you’ve worked hard and given it your best, be proud of that. If you won the title, be gracious winners. Congratulate the other teams you beat, and if the competition was intense, be glad. It feels better that way.

If you missed out on your goals, be gracious non-winners, too. Go congratulation that team, or teams, that finished above you and tell them they did a good job, because they did. All things being equal, we all know that a little luck plays into how it all ends. Maybe next year, you’ll be the ones being congratulated on winning the title. Let’s hope so.

The post Push for Points appeared first on Hot Rod Network.

Many times a team will change from a stock lower, big spring front end designed car to a coil-over car, or the other way around. If you have perfected your balance with one of the systems and have the need to keep the same basic balance, then you need to be able to match the new spring rates to the old ones.

To be honest, you need to determine if other aspects of the new car might be different than the way the old car was built, like placement of the rear springs, weight distribution, front geometry, etc. Here we will only be working with the spring rates, but keep the above in mind when going from your present car to a different one.

The process involves converting the current spring rates to wheel rates. To do this, we need to use a bit of math, but it is doable for the average guy using a scientific calculator. Remember that we are working with motion ratios and shock angles with the coil-over, and only motion ratios with the stock type spring suspension. The motion ratios as well as the cosines of the shock angles will be squared in the process.

What To Measure – First, measure your lower control arms to determine the length of the control arm, which is the rotational length. For the stock type arms, we need to find the shortest distance from the ball joint to a line between the centers of bushings, not from the ball joint to the front bushing. Then measure the distance from the center of the ball joint to the center of the spring pocket.

For coil-over cars, we will be measuring from the ball joint to the inner mount that lies at nearly ninety degrees off of centerline. Then measure from the center of the ball joint to the center of the mounting bolt for the bottom of the coil-over.

Next for coil-over cars with the car at ride height, measure the angle of the shock/spring from vertical. This will be used in conjunction with the motion ratio to determine the wheel rate.

Once you have all of your measurements and have them written down, we need to find the Wheel Rate for each front wheel. These may be different due to using different spring rates on each side, and/or having different motion ratios or shock angles. When we have determined the fractional number for each side, we’ll call that the Net Motion Ratio, or NMR.

From Big Spring Wheel Rate – If your present car is a big spring design, then we will measure the Right Front wheel first. For example, we have a 15.50” control arm length, and 6.50” from BJ to spring bucket center. We subtract 6.50 from 15.5 and get 9.00. This is the distance from the spring bucket center to the pivot line. Divide 9.00 by 15.50 to get the motion ratio, then multiply that by itself to square it. This is the motion ratio squared and the NMR for the RF wheel, or 0.3371. There is no spring angle here as it is mounted at nearly 90 degrees off the lower control arm.

To get the WR, we multiply the NMR times the spring rate, say 500 lb/in to arrive at a WR of 168.55 lb/in.

If your LF suspension has the same dimensions, but you run a 600 lb/in spring, then we multiply the NMR times the spring rate to get a WR of 202.26 lb/in. Remember those numbers. We will use them to determine what spring rates we’ll need in our new coil-over car.

Calculating Coil-Over Spring Rate – Now we need to determine the spring rates for our new coil-over car that will yield the same wheel rate as the old car. We measure the RF lower control arm and find that it is 17.50”. We measure from the ball joint to the center of the mounting bolt at the bottom of the shock and get 2.50”. We subtract 2.50 from 17.50 to get 15.00. Divide 15.00 by 17.50 to get a motion ratio of 0.8571 and multiply it by itself for a MR squared of 0.7346.

Next we measure the shock angle and find that it is 18 degrees off of vertical. We need to find the cosine value of an 18 degree angle and it is 0.9511. We also square that number to arrive at 0.9046. To find the NMR for the RF of our coil-over car, we multiply the MR squared number by the shock angle cosine squared number to get 0.6645.

If we then divide our coil-over NMR number into our big spring wheel rate for the RF (168.55), we come up with a spring rate for our coil-over car of 253.64 lb/in. We can use a 250 lb/in spring and be very close.

For the LF the process is the same as for the RF. Our lower control arm is 15.50”, our ball joint to spring mount is 2.50”, so we subtract 2.50 from 15.50 to get 13.00. We divide 13.00 by 15.50 to get a motion ratio of 0.8387 and then multiply that by itself. Our MR squared for the LF is 0.7034.

If we have a shock angle of 20 degrees for the LF, then we have a cosine value of 0.9397 and squared equals 0.8830. Multiply that by the MR squared and we have a NMR for the LF of 0.6211.

We now divide the NMR for the LF into the previous cars WR for the LF and we get a coil-over spring rate of 325.64 lb/in. So you would use a 325 lb/in spring in the LF.

If you are going from a coil-over car to a big spring design, the process is reversed. Find your wheel rates for the coil-over car first and then convert those to spring rates for your big spring car.

This may seem a bit complicated, but if you understand the process and keep good notes, it will go easier with time. This process isn’t just for converting from big spring to coil-over. At times for the same design, the dimensions can be different for two coil-over cars, or two big spring cars. Use the same process to determine if you need different springs.

Switching Between Installation Ratios – It is common for a team to buy a new car from a different manufacturer or move to a new class where the cars are constructed differently than what we are used to. What often changes is the installation ratio at the front of the car and spring base at the rear.

We have covered the front conversion process, but what about the rear? There is no exact formula for conversion of rear springs, but here are some tips that might help you make changes based on the difference in design.

If the new car is a coil-over like in the above example for front end conversion, then chances are that the rear springs are spaced wider than they were on the big spring car. Most cars with rear big springs have them mounted on top of the rear axle tubes and they are generally about 35 inches apart. This is the spring base.

For coil-over cars, the location of the top mounts of the coil-over is the spring base because the car sits on the tops, not the bottom. A typical late model coil-over car has the bottom mounts about 42 inches apart. The spring angles average about 5 degrees on each side and the lengths of the coil-over’s are about 18 inches between the centers of bolts use to mount them.

We can calculate the coil-over spring base by using a little math. To find out how much the top of the shock is tilted in towards the center, we multiply the Sin of the angle, 0.0872 for 5 degrees, times the shock length, 18.0” to get 1.56”.

If we double that and subtract the answer from 42, we get the coil-over spring base at the top of 38.86”. So, our coil-over car has a wider spring base than the big spring car had. This means we will have a stiffer rear suspension if we use the same spring rates.

The coil-over combined spring rate needs to be softer than what we used with the big spring car, but by how much? We can use the ratio of the two spring bases to find out how much softer we need to be.

If we divide the big spring base by the coil-over base, we get 0.9007. We need to square that number to get 0.8112. If our combined spring rate for the big spring rear suspension was 500 pounds, then we only need a combined coil-over total spring rate of 405 to have the same stiffness. To get that, we multiplied 500 by 0.8112.

A Caution: Spring split in the rear has a pronounced affect on roll stiffness, so keep that in mind when evaluating going from big spring to coil-over. The above example is considering that the cars both have the same spring rates on each side. If the first car has an existing spring split, you could multiply each spring rate by the 0.8112 multiplier to arrive at individual spring rates for each side while keeping the spring split.

Conclusion – If you have a racing buddy who is doing well and you want to run his setup, make sure you know the relationship of the motion ratios and spring angles when comparing the two cars. His motion ratios and spring angles may well be very different than yours and the setup may not translate well.

When changing to a different car, you must take into account the differences in the way the cars were constructed, including the moment (roll) centers. Most times when a team changes cars and all of the springs are positioned in exactly the same locations and angles, if there is a marked difference in handling, it most times involves a difference in front end geometry design.

Sources:

Afco Racing
www.afcoracing.com
800-632-2320

Allstar Performance
www.allstarperformance.com
269-463-8000

Integra Shocks and Springs
www.integrashocksandsprings.com
800-472-3464

Smileys Racing Products
www.smileysracing.com
866-959-7223\

Speedway Motors
www.speedwaymotors.com/CT715
855-313-9175

The post Making Different Cars Equal by Matching Spring Rates appeared first on Hot Rod Network.

Through the years we have heard various myths about the pinion angle providing bite off the corners. I have experimented with pinion angles while running a Nascar late model on a rear wheel dyno and found little in the way of power gains from more or less angle.

Here is what we know. Drive line angles that are not correct are a cause of vibration and power loss. If your race car must have drive line angles from a design standpoint, the angle of the drive shaft to both the transmission output shaft and the pinion shaft should be equal and also opposite. And, the angles should be kept to a minimum if at all possible.

When a team concentrates just on the pinion end of the drive train, things can get ugly, and here is why. A drive shaft system is somewhat complicated, but not so much that we cannot understand it. There is a video online that shows what happens when the alignment is not correct. It is almost violent if you understand mechanics and dynamics.

To view the video for yourself, just search YouTube for “Driveshaft Angle and Phasing”. There you will learn why the angles of the transmission output shaft to the driveshaft, and the pinion shaft to driveshaft angles need to be the same (equal) and in the opposite direction.

A friend of mine in the industry and I have been talking about setups for his car on and off for a couple of years and in July of last year he asked me about pinion angles. He runs a big block Northeast dirt modified. He explained that he was running about 4 degrees downhill to the front with his pinion. I asked him what his transmission output shaft angle was.

Evidently, the tranny was downhill to the rear by 6 degrees and with the pinion angle running down to the front, his situation represented the worst case scenario. Just look at the video and you’ll see why. With the angles he had, as the transmission shaft turns one full revolution, the pinion would speed up and slow down twice per revolution. At 6-7,000 RPM, this becomes obscene. In my friend’s car, it created a harmonic vibration that he always assumed to be just a part of the race car.

Here is how we can determine what we have, what to do and how to fix it. You will need to put your car up on blocks or boxes so that you can get underneath of it safely. We need to take several measurements.

The attitude of the car needs to be the same as it is when running around the race track. So, if you are running on bumps, put the front of the car down to where it would be while on the bumps. For my friend’s dirt modified, he jacked it up in the front and on the left side and down on the right just like it would be during the race.

Also consider the change in pinion angle if you run a lift arm or pull-bar. Those pieces of equipment will change the pinion angle as they move under acceleration. When power is applied to the drive train, any miss-alignment will cause the most damage. You might want to measure your pinion with the rear end at the position it will be under full acceleration.

How And What To Measure – First measure your transmission output shaft angle. There is an easy way to do that. Your engine is in line with this part. The valve covers, unless they are of a strange design, will be parallel to the block deck, which is parallel to the driveshaft which is parallel to the transmission shaft. So, just lay an angle finder on the edge of the valve cover, read the angle and write down the number. Also note which way it is inclined, down to the rear or up.

Next crawl under the car and lay your angle finder on top of the driveshaft and measure the driveshaft angle and note the inclination. Then measure the pinion angle and also note the inclination. To get the pinion angle, you might have to use a straight edge placed against the flat part of the flange with the angle finder against that.

We’re not done yet. Driveline angles can occur from any view. We have just measured the angles from a side view, but what about the top view? Now we need to look at that scenario.

To measure top view angularity, we need to do some lateral measurements to the center of the tranny shaft and the center of the pinion shaft. If you have a straight rail car and know that the rail is parallel to the centerline of the chassis, this will be easier. If not, you need to setup a string line that is parallel to the centerline.

Measure from the centerline or straight rail to each of the above mentioned shafts using plum bobs or similar devices to make sure the measurements are correct. We need to determine if the two shafts are in line, or if not, how far they are out of line.

For most offset late models, I have found the two to be out of line by 1.0 to 1.5 inches. For a 40 inch driveshaft that is out of line by 1.5 inches, the driveshaft to pinion and driveshaft to tranny shaft angles would be 2.15 degrees. That is plenty of pinion angle and almost too much by today’s standards. But the good thing is that they are equal and opposite.

If that were true for your car, then you would not need any side view angles in either the pinion or tranny. So, you could place the tranny shaft, driveshaft and pinion shaft in line with no side view angular difference. That is because the U-joints don’t really know which direction they are lined up at, only that there are equal and opposite angles in their relationship to the driveshaft.

How To Adjust The Angles – Now that we know what the angles are, let’s see how we go about making changes. Let’s assume that from a top view, the tranny is in line with the pinion. So, we only need to work with the side view angles.

For an example, using my friend’s angles, we have an engine that is downhill to the rear by 6 degrees and the pinion going downhill to the front by 4 degrees. What I recommended was reducing the engine angle, but it was going to be impossible to run it uphill to the rear, so he re-shimmed the motor mounts until he got to 2 degrees downhill to the rear.

Next, it was fairly easy to change the pinion angle because he had a three link rear suspension. Now this is going to sound strange to many old timers, but we rotated the pinion until it pointed uphill to the front by the same 2 degrees. Now the angles were equal and opposite. But, you say, “we cannot run the pinion uphill!” Yes we can. Nothing in the dynamics world says we can’t. In this case we proved it.

If you have other designs for your rear suspension, you’ll need to get creative when changing the pinion angle. For leaf spring or truck arm cars , there are wedges made to varying degrees you can use to place between the spring and the pad on the axle tube. This will rotate the rear end and pinion to change the angle to the drive shaft.

For stock four link rear suspensions, you’ll need to get even more creative. Since the alignment of the driveline is so important, it is not out of the question to cut and re-weld the suspension links to change the lengths in order to rotate the rear end and change the pinion angle. Just do it in a safe manner. Make good welds or have a professional do it.

As for my friend, the result of making these changes was the elimination of the vibration he had felt forever. He also told me that the forward bite improved. I envisioned that with the driveline out of alignment, it was like spiking the throttle on and off many times per second and that caused the rear tires to lose grip under power.

The truth is this, the speeding up and slowing down of the pinion shaft with each revolution of the engine that is due to miss-alignment happens not only on acceleration, but all of the way around the track as long as the engine is connected to the rear end.

As the season comes to a close, you might want to make a note to inspect your driveline in the offseason and take a few measurements. If the alignment is not correct, please take the time and effort to make it right. The performance gains could be substantial.

Sources:

Allstar Performance
www.allstarperformance.com
269-463-8000

Coleman Racing
www.colemanracng.com
800-221-1851

DMI / Bulldog Rear Ends
www.diversifiedracing.com
717-397-5347

DRP Performance Products
www.drpperformance.com
888-399-6074

Frankland Racing
www.franklandracing.com
888-873-2736

Moser Engineering
www.moserengineering.com
260-726-6689

Quick Performance
www.quickperformance.com
515-232-0126

Winters Performance
www.wintersperformance.com
717-764-9844

The post Step-by-Step Drive Shaft Alignment appeared first on Hot Rod Network.

In modern day setups, the springs are being used in ways never before imagined. It is more critical than ever before to know the exact spring rate you are installing. And, to further complicate that, the rate the car “feels” can vary with how that spring is installed.

The very first thing to consider when talking about what rate springs to use in your race car is knowing exactly what the spring rate is for each of your springs. You must test each spring and do it in the proper way. We need to know the spring rate of our springs at the range that they will be working within in conjunction with the corner it will be working with.

That means that if we have a 200 lb/in rated spring, the actual rate might differ when installed in different corners of the car. That is because its range of motion would necessarily be different at each corner, so as we test the spring for it rate, we could have different rates for each range of motion. As long as we know that, we are OK.

What Occurs At Each Corner – Let’s discuss how we evaluate each spring by analyzing what happens at each corner of the car for different setups. Keep in mind that each car is different due to different setups, and different uses, i.e. dirt versus asphalt, and conventional versus bump setups.

For all setups, dirt or asphalt, the RF spring is always in compression, or bump, so we would compress that spring to the installed height and then further compress it to its greatest useable length to find the average rate within that range. Remember that there is an installed motion ratio and the spring is moving less than the wheel, so we don’t necessarily need to compress the spring as much as the wheel moves.

For example, if you have a Late Model car and the coil-over is mounted 2.5” in from the ball joint and the lower control arm is 17.5” in length, the motion ratio is 0.857, or 85.7% of the wheel travel. If the shock is mounted at 20 degrees it moves even less. The cosine of 20 is 0.94, so the spring now moves 94% at that angle than if it were mounted straight up. Multiply those two together and you get 0.805, or 80.5% of wheel travel. If your wheel travel was 3.0”, then the maximum spring/shock travel is 2.42”.

For a conventional big spring car, the motion ratio is much different. If you have a spring mounted 6.5” from the ball joint and the lower arm is 15.5 inches long, then the motion ratio is 0.58, or 58% of the wheel travel. For 3.0” of wheel travel, the spring will compress only 1.74”.

Here is where a good quality travel indicator becomes very useful. When working with bump stops and/or bump rubbers, finding the loads that are developed on those bumps requires exact knowledge of shock travel, which tells us the spring travel too on a coil-over installation.

The LF spring could either be in slight compression, rebound in a dirt car, or a high amount of compression when used with bumps. Again, we need to know the range of compression we are going to be working within. So if you are using bumps, then the spring is compressing all of the way onto the bump, plus the amount the bump is compressing.

The RR spring is also mostly in compression and would be compressed initially to ride height and then up to 3-4 inches further, depending on the shock travel for coil-over cars, or shock travel verses spring travel for a big spring car where the spring is mounted separate from the shock. Remember that for bump setups on asphalt, the right rear spring will be much stiffer and travel much less than a conventional rate spring.

The LR spring moves the least compared to the other four springs on the car for all types of setups except certain dirt setups. It is in some rebound on entry and some compression at mid-turn. This spring would be rated by compressing to ride height and then moved up to 2 inches up and down.

For dirt car applications, this spring may rebound quite a bit as the left side jacks up for some slick track setups. In this case, the spring may well be very near or past the free (unloaded) height at mid-turn and compressed down the straightaway.

The Ten Step Process – Once we determine the amount of spring travel and the installed height, we can then rate the spring. Here are the steps you take to accomplish that.

Step One – Write down the installed height and amount of maximum compression for each spring related to the corner of the car. You should have for example, RF 175 spring #4 @ 9.687” ride length / 6.625” maximum compressed length, and so on for each spring in your inventory.

Step Two – Work with one spring at a time. Install it in the spring rater. Chose which corner you wish to rate the spring for. If you have a 175 lb/in spring, you could rate it for the LF, RF, RR and LR corners because it could be used for any of the four if the length matched the shocks, etc. Anyway, chose which corners it might be used on.

Step Three – For the corner you wish to rate it for, compress the spring to the normal ride height length. Zero your scale if so equipped or write down the load. Also zero your travel indicator, or write down the measurement.

Step Four – Now compress the spring in increments of ½ inch (0.50”) and record the load at each increment. Go until you reach the maximum compressed length for a spring of that rate mounted at that corner. Record the load at that point.

Step Five – Relax the spring and re-measure all of the loads to make sure they are the same as the first time. Re-measure until you get two sets of numbers that match.

Step Six – Now that you have recorded the loads, subtract each set of increments to find the gain in load verses distance. The load at the first ½ inch of travel will be subtracted from the original ride height load. Then multiply each of the ½ inch increment loads by two to find the rate of the spring in pounds per inch. Record these rates.

Step Seven – Now subtract the final load reading taken at maximum travel from the load at normal ride height and divide by the maximum travel to get the average spring rate in pounds per inch. This number should compare with the individual readings you took at half inch increments multiplied by two. If not, the spring is not consistent in its rate through the full range of motion for that corner.

Step Eight – Choose another corner of the car that this spring might be used on and repeat steps Three through Seven being sure to record your results.

Step Nine – Rate all of your springs using the above methods and write down the results.

Step Ten – Make a listing of your springs, the corner they will be used on, and the rates per corner. That way, when you make a spring change and use that spring for a particular corner, you will know exactly what spring rate is influencing the car.

Rating Springs With Bumps – To further complicate, or refine this process, you can rate the springs while they are installed on the shock if it is a coil-over. Just use a spring rater that is designed to mount the shock to it and follow the process described above.

If you run bump springs, you can rate the ride spring in combination with the bump spring. The difference in the procedure is that once you get the ride spring compressed down to the bump spring, the intervals must change to 0.125”, or 1/8 of an inch per reading.

The reason is because the total travel of the shock on a bump spring is only about 0.250” to 0.500” maximum. Some of you might want the bump spring load information from the bump springs and that is read directly as the load at maximum travel minus the load recorded where the ride spring just touches the bump spring.

Problems With Spring Rubbers – Some teams might still use the spring rubbers to change the spring rate. These are the rubber/silicone inserts that go between the coils of the ride springs and not the bump rubbers. These add spring rate to the ride spring and the amount varies radically based on the amount they are compressed.

The success we will have using spring rubbers is only as good as our knowledge of how much the spring rate changes. The rate change for a particular size and hardness of spring rubber is different for each different rate and design of spring and for different amounts of preload on a certain rate of spring.

If I install a “25 pound per inch” spring rubber in a 200 pound spring, the amount of rate change will be different as the magnitude of pre-load on the spring changes. That is because a 200 lb. per inch rated spring that holds up 950 pounds will be compressed 4 ¾ inches whereas a 200 lb spring that holds up 500 lbs. will only compress 2 ½ inches. This means there is a different gap between the coils for each application and the spring rubber will be compressed more in the spring that supports 950 lbs. than the one that supports 500 lbs.

It is also true that if we change to a 150 lb./inch rated spring in place of the 200 lb. spring, the compressed height on the corner holding 950 lbs. will be 6 1/3 inches and the spring rubber will be compressed even more yielding a greater spring rate of its own.

Correct Way To Rate A Spring Rubber – The correct way to rate a spring rubber for a particular use is to do it like we rate a spring, in a spring tester. We first rate the spring as outlined above.

Next we relieve the pressure on the spring and install the spring rubber. We then repeat the process and compress the spring to its ride height and go through the same process. Whatever the increase in loading is over the “spring only” loading yields the rate of that spring rubber for that corner of the car and that particular spring.

We can have several springs that are rated the same in pounds per inch, but have a different number of coils and/or diameter of wire. This difference in construction means they will be different in the size of the gap between coils and therefore produce a different spring rate for the spring rubber.

How To Rate A Leaf Spring – I have never approached this subject before. There is a more complicated way to rate a leaf spring, and an easier way that might not be precisely accurate, but close enough. First let’s explain the more accurate way.

If you could remove the spring, place it in a fixture that would hold the ends without creating binding, that allows the spring to compress and rebound freely, then you could rate that spring.

You would need to design this fixture so that you could mount the spring with the eyes up (concave upwards) and be able to place a scale pad under the center where the axle is attached. On the scale pad would be placed a jack.

Just as in the above example for coil springs, the spring would need to be pre-loaded to its ride height position however you could do that. I would pull a string across the center of the eye bolts and measure to the top of the top leaf on the car at ride height and replicate that on the scale.

Then jack the spring in half inch increments and record the loads just as we did with the coil springs. Then determine the spring rate of the leaf spring. But what if you don’t have those kinds of tools available?

A spring is measured for spring rate by causing the spring to compresses a known distance while measuring the load increase due to that movement. If we can move the leaf spring a known distance while it is on the car and then measure the load change, we can then know the spring rate.

This gets tricky because there are several ways to mess this up and influences that make this inaccurate. So, we need the rated spring to support more load while being compressed in measured amounts. Start off by chaining the other spring to the frame so that spring cannot rebound.

Once you have done that, place a scale and hydraulic jack under the rated spring. Remove the wheel from that side and return the jack to the original height it was before removing the wheel. Measure the distance between the top of the spring at the axle tube and the frame directly above it. Record the load reading on the scale.

Now, jack up the rated spring until the distance between the top of the spring and the frame reduces by ½ inch and read and record that load. Keep jacking in ½ inch increments until you have gone three inches. Take each ½ inch increment difference in loading and multiply times two to get the spring rate in pounds per inch at each increment.

Now you have rated that spring. For many leaf springs, the rate may well be progressive meaning it will increase with additional travel. Use the average rate for the range of travel you will experience for that corner at your race track.

Conclusion – Many times teams have rated a spring and been surprised at the outcome. A spring that is 10 or 15 pounds different than you expected can make a big difference in handling when used at the rear of the car.

As with all setup parameters of your race car, know and record the spring rates in your inventory. Like I have said in the past, the car rides on the springs basically, and these are your connection to ideal loading of the tires, which as everyone knows, is the secret to the best setup.

The post How To Correctly Rate A Spring appeared first on Hot Rod Network.

At some point in your team’s life, you might venture out to different tracks than the one you race on regularly. When you do that, you must learn how to setup for those tracks. If they are much the same as the one you raced on, not much will change. But, if they are very different, you might have a difficult time dialing the car in.

There is seldom much time to make adjustments to your setup before qualifying at the new track, so here are some helpful hints on what to expect and some tips on doing some prep before you go so that you will be better prepared.

Types of Race Tracks – There are different types of race tracks and I wanted to define those before we get into the meat of the subject so we’ll know which direction we want to go with changes. I’ve had to work with teams that ran traveling series a number of times and I’ve had my behind handed to me more than once when I couldn’t get adjusted to a different type of track in time to go racing. So, here is some of what I have learned and been taught.

There is the flat track configuration verses the high banked track, and there are varying degrees of banking in between. Then there are longer verses shorter tracks. The longer ones have more overall speed as well as higher speeds through the turns. It goes without saying that you’ll need to re-gear the car for the longer and faster tracks.

The transitions from straights to the banking can be much different between race tracks with similar banking angles. For some tracks, the inside stays relatively level and the outside rises up to form the banking. For others it is the opposite, the top remains more level and the bottom drops down to make the banking. And for many, it is a combination of each of the above.

This difference in shape and size makes a big difference in how you setup your car in terms of springs and shocks. Finding the basic balance for mid-turn handling is the same process for each of the track configurations, but the stiffness of the springs and shock values need to be tailored to each track.

Going From Flat To Banked – Banked tracks have more G-force, more mechanical downforce and have generally better bite off the corners than do flat tracks. First, with more G-force, the balance must change. You were probably more concerned with bite off the corners on your flat home track, but that won’t be as much an issue with the banked track.

With a higher lateral G-force caused by the higher corner speeds, the overall chassis roll will increase, but the rear will increase more than the front. So, we must control that added roll by doing one, or a combination, of the following.

We can increase the rear spring split, i.e. softer LR spring and/or stiffer RR spring. We can also raise the panhard bar to decrease the rear roll by increasing the rear stiffness. We also need to stiffen and/or rearrange the front spring rates.

If you ran a softer RF spring than the LF spring, you will need to reverse that. Tracks that rise up on entry are hard on the RF spring. You’ll need to stiffen that, even if you run bumps.

If you ran a higher range of cross weight, you need to drop down to the lower range. For example, if your front to rear percent of total weight were 50%, and you run 58% of cross weight at your flatter track, you probably need to drop down to 51.7% or so for the high banked track. The higher, equal to the left side percent, cross weight never worked well for me on high banked tracks.

Going From Banked To Flat – What you read above is pretty much in reverse of this scenario. You are probably used to flat footing it off the corners at your high banked home track because you always had that high amount of mechanical downforce loading your tires. They gripped well because of the extra loading. Now you’ll need to make changes not only to your setup, but in how you drive the track.

If you do the reverse of the above for setup, you will also need to develop bite off the corners. Whereas we did not want much if any rear steer on the high banking, we’ll need to create some steer to the left on acceleration off the corners to offset the tire slip that will come.

We have outlined various techniques for doing this over the past few months and years, so here is a recap. If you allow your car to squat, a higher left trailing arm angle will cause the LR wheel to move back during squat and cause rear steer to the left which will counter the tire slip.

If you like anti-squat, you can move the third link to the left to put more of the displaced loading caused by the third link angle to be placed more to the left side of the rear end. This loads the LR tire more than before, which creates more bite off the corner.

The most important thing is the way the driver applies throttle. On the high banks, you could probably go to full throttle in one quick motion. On flatter tracks, you’ll need to slow that motion down quite a bit. It is called squeezing the throttle and you need to educate your foot.

Inside Drop To Outside Rise – If you are going to a new track where the outside rises up to form the banking, the RF shock compression and spring rate must be increased to control the upward motion of that corner of the chassis. A typical example is Daytona, not that you’ll be running your late model there any time soon, in that the track rises up to form the 31 degree banking. It hammers the RF corner of any car running there.

The same track that rises up on entry also lays down on exit. The outside must come down to form the lower straight away banking, so the RF falls off a cliff so to speak. When this happens, both the RF and the LR shocks must rebound quickly in order for the tire to maintain contact with the track surface.

So, you’ll need to run less rebound in the RF and LR shocks. I have witnessed this happening at some tracks. If you ran a stiff rebound LR shock to free up a car on entry to your track, at this type of track you’ll need to go back to a more conventional rebound rate.

Outside Rise To Inside Drop – When you run a track where to get the banking, the inside drops, the left front shock rebound rate must be less than “normal” to allow that wheel to rebound and stay in contact with the track surface on entry.

Also, the RR shock must also have less rebound rate to allow it to droop as the left front of the car follows the dip in the track. If not, the car could get tight from load being lifted off the LF and RR tires during this transitional phase. Less loading for that diagonal verses RF to LR means a higher cross weight momentarily.

What goes down must come up so to speak. That dip on entry becomes a rise on exit off the corners. Now the LF will be forced upwards quickly and we need to think about that motion. If we try to control that, more load will be applied to the LF and RR corners and that would reduce the cross weight loading causing a loose off condition.

Rather than controlling that rise at the LF, maybe we should allow it to happen, as long as it doesn’t cause our ride or bump springs to go into coil bind. A little less compression setting in our LF shock might be welcome in allowing that corner to transition into the rise in the track on exit.

Going From High Banked To Super High Banking – For super high banking, there is a greater amount of mechanical downforce, and this makes the car travel more, well, down. If you run conventional springs, then you must stiffen them quite a bit.

When we used to run Bristol, which was 26 degrees in banking in the late ‘90’s and early 2000’s (not the advertised 36 degrees), our Goodies Dash cars and the New England Tour Modifieds had to more than double their spring rates to keep from bottoming out.

For example, the banking at Slinger is somewhere around 16 degrees from the reports I have gotten back from competitors who physically measured it, and those cars must increase their conventional setup front springs by about 1.5 times the normal 12 degree track rates.

If you are running bump rubbers, or bump springs which are now becoming much more popular, you must increase the spring rate of your bumps. The normal bump spring rate of 1200 to 1500 ppi must now be upwards of 1800 to 2200 ppi rates, or they will coil bind.

Circle Track To Road Racing – I threw this in because some teams want to learn the road racing side of stock car racing. In Cup racing, they now run Sonoma Raceway and Watkins Glen International road racing courses. So, if your desire is to someday run in Cup either as a driver or crew chief, you’ll need to know a few things about road racing setups.

First off, in case you didn’t know it, you’ll be turning left and right. What works for the left turn must also work as well for the right hand turns. So, the three areas that need to be equal are: 1) front geometry, 2) spring rates right verses left, and 3) weight distribution. Let’s take number one first. The front geometry includes several settings. First off, the Moment Center must be centered and move equally to the side for each direction of turn. And, it must be designed to not move very far from centerline.

Next, continuing with the front geometry, the front cambers must both be negative. This hurts the inside tire going through each of the turns. And, the Ackermann must be equal for each direction you are turning. So, if you adjusted the steering arm lengths to set your Ackermann and ended up with different length arms, that is a no-no for road racing. You’ll have to move the steering rack fore or aft to set your Ackermann and keep equal length steering arms.

Also, you cannot use caster split on a road course. The caster must be the same on both sides and most road racers use more caster than you would normally use. And along with that, the degree of spindle inclination must be equal for each of the spindles, whereas we usually use different degrees for left verses right spindles.

For number two, the spring rates must be equal for the front springs, and the rear springs side to side, not front to rear. Most road racing late models use high rear spring rates about twice the normal conventional spring rates. Even then, the roll is too much, so a rear sway bar is needed.

Finally, for number three, the overall weight distribution must change when running a road course. The left side percent can no longer be 56 or 58 percent. You’ll need to work towards equal left and right side percent rates.

And, the cross weight must be 50% for a road racing car. That way, it is the same for right and left hand turns. So, if the front to rear percent dictates the correct cross weight we need to run for circle tracks, then we must develop a front to rear percent number in our road racing car that will want 50% cross weight.

Conclusion – We have tried to get you thinking about what changes will be needed when you travel to a different race track for the first time. You might be able to think of other things that must change, but with these suggestions, you’ll begin to understand the dynamic differences between tracks of different configurations and sizes.

If you can get good at this, you will have much more fun with your travels and your team will be much more successful. Try to be prepared by having a variety of springs available in the range that works for the new track and use adjustable shocks so you can fine tune that balanced setup for the transitions. Most of all, have fun with your travels. It’s the journey that counts, not necessarily the destination.

Sources:

Afco Racing
www.afcoracing.com
800-632-2320

Allstar Performance
www.allstarperformance.com
269-463-8000

Capital Motorsports Warehouse
www.cmwraceparts.com
800-278-2692

Coleman Racing
www.colemanracng.com
800-221-1851

Day Motorsports
www.daymotorsports.com
800-543-6238

DRP Performance Products
www.drpperformance.com
888-399-6074

Integra Shocks and Springs
www.integrashocksandsprings.com
800-472-3464

PitStopUSA
www.pitstopusa.com
866-722-3432

Smileys Racing Products
www.smileysracing.com
866-959-7223

Speedway Motors
www.speedwaymotors.com/
855-313-9175

The post How To Change Your Setup For Different Race Tracks appeared first on Hot Rod Network.

There is an apparent problem with the way crate rocker arms are being checked and the way some rockers are being manufactured that are in conflict. We conducted a study at the request of a racer who experienced the problem first hand. The results are very interesting. There is a serious problem associated with crate motor rocker arm ratios. If you run a crate motor or you are a tech official who checks crate motors, you need to read this and understand this problem. Honest racers are being DQ’d for having “legal” rocker arms installed on their crate motors. And for some reason, this is associated with the GM crate motors and not so much other crate motors so say the tech officials. We’re not so sure it doesn’t affect both.

This might be thought of as a procedural rather than a cheating problem. As we talk you through the origin and progression of this situation, keep in mind that we found that no one, racer or manufacturer, had or has any intention of cheating the system.

This year, certain racers who run at Nashville Fairgrounds were being disqualified for having non-compliant crate motor rocker arms. The rockers were being checked on a rocker checker manufactured by a company in St. Petersburg, FL. This checker, we’ll call the Precision checker, is currently being used throughout the Southeast at tracks like New Smyrna, Five Flags, Nashville Fairgrounds, etc.

That rocker checker is built to the same specifications as a true engine and raises the push rod 0.100”. The “valve” end of the checker then moves a fake valve using a weak spring to hold everything in place. If the “valve” cap moves 0.150” then the rocker is a 1.5 ratio (0.100 x 1.5 = 0.150”).

I double checked the dimensions of the checker myself and found it to be a very accurate duplication of how the parts in a real crate motor work based on push rod angle versus valve stem angle and rocker height. But there is a problem associated with using this checker that I will explain in a minute.

There is another rocker checker made by General Motors for checking 1.5 and 1.6 ratio rocker arms made for those motors. With that device, we’ll call the GM checker, you lay the rocker onto the fixture and the pivot shaft moves along a stud. The push rod end cup fits onto a stationary push rod shaped shaft and both must fit together perfectly. On the valve stem side, the rocker roller fits into a fixed shaft with a cup shaped end. Again, the roller must fit perfectly into the cup in order for the rocker to be deemed legal.

Here is the problem. Some rocker arms fit the GM checker, but do not calculate as a legal ratio on the Precision checker. I obtained one of the Precision checkers and an area engine builder had one of the GM checkers. So I went to work checking multiple rocker arms including the actual one that was the reason for the DQ’d in Nashville.

What I found was that the aluminum rocker that was the reason for the DQ is stamped as a 1.6 ratio rocker. This rocker checked on the Precision checker at a 1.7+ ratio, but still fit the GM checker. Moreover, when I checked this same rocker on an actual motor using precise methodology, it evidently flexed because it checked a legal 1.6 ratio.

Upon further research, I discovered that some years ago, the highest level engine builders working in Cup realized that the aluminum rockers were flexing enough to cause a loss of HP. They converted to steel rockers and the problem went away.

Some manufacturers of the rockers that are intended to be run on the crate motors also realized this problem. They designed a rocker that fit the GM template but operated at a higher ratio when not under valve spring loading, hence the DQ using the Precision checker.

That same DQ rocker was reduced to the legal rocker ratio when loaded by the stronger valve spring. It is actually legal on the engine, but not on the Precision checker that cannot load the rocker the same way a stiff valve spring does.

So, if you run one of these rockers, you are technically legal, but illegal if they are checked on the Precision checker. The only thing you can do is run a specified rocker and at New Smyrna the rules recommend the Crane Cams rocker. We checked a Crane rocker and it check legal on both checkers. Does that mean it checks out at the stamped ratio on the engine, maybe, maybe not. We only “engine” checked the rocker that was deemed illegal at Nashville.

In our opinion, it doesn’t seem fair to DQ a team when technically they are not cheating if their rocker checks to the correct legal ratio on the motor. The problem comes in the enforcement of the rules. It is very difficult to check the rockers on the motor. I had a difficult time with the engine mounted to a stand inside an air conditioned building.

The lead tech officials I spoke with told me they were not going to change the way they tech rocker arms. So, as a racer, you can either run an aluminum rocker that checks OK, but might give up a little valve lift on the motor, or run steel rockers like the Cup guys do. It’s as simple as that. But now at least you know the situation and can act accordingly.

The post Crate Motor Controversy: Rocker Arm Fiasco appeared first on Hot Rod Network.

There are basically three types of teams. Those who win on a fairly consistent basis, those who are close to the front, but almost never win, and those who wonder what the first two are doing to go so fast. There is a fourth group that doesn’t relate to our discussion. Those are the teams that are just happy to show up, have equipment that will never be able to compete, and are completely satisfied with the situation. And I am happy for them.

But this presentation is for those who really want to improve their setups and be more competitive. As we enter the last few races of the season, the second group needs to tweak their setups to gain that couple of tenths that will put them at the top of the heap.

The third group has nothing to lose and needs to make major changes in order to move up the lap chart. And now is the very best time to do it. Experimenting during the late part of the season when you are fifth to tenth in points or higher could help you find that speed to make the start of next season more fun. So, let’s see how we can improve our setups.

The most basic rule of handling and speed for a race car lies in increasing the speed we can go through the middle of the turn. It has been said before, and rightly so, speed gained in the turns will be carried throughout the lap. This is true for both circle-track racing and road racing. The Mercedes F1 cars are faster in the turns and slower on the straights. They win a lot.

Mid-Turn

We start out by solving our mid-turn handling problems. We do this because our mid-turn handling affects both entry and exit to a large extent. A car that is tight in the middle will most likely be tight into the turn and tight off. If excessively tight in the middle, the car could be loose off as a result of the tight-loose syndrome.

To change mid-turn balance, we can do one of the following:

1. Raise or lower the rear Moment Center (MC) by moving the panhard bar or J-bar up or down. For leaf spring cars, we can raise or lower the actual spring, but that is not an easy thing to do. Metric four-link cars also have a tough time changing the rear MC height and must rely on other methods to change the balance.

2. You can change the rear spring rates. Softening the right rear spring, and/or stiffening the left rear spring will increase the rear roll and will tighten the car, as will softening both rear springs. The inverse is true, stiffening the RR spring and/or softening the LR spring will loosen the car.

3. Softening the front springs will help the car turn, but to a lesser degree than making rear-spring changes. Spring split at the front also has less affect and has more influence on entry characteristics than on mid-turn.

4. Installing larger or smaller sway bars will have an effect on handling. The stiffer the bar, the less the front will want to turn. So, to help cure a tight car, we can go to a softer sway bar.

5. Increase or decrease the crossweight percentage. As we make changes to the crossweight, we affect the handling of the car, and we can easily make the car neutral in handling by making crossweight changes. But this is not the ideal method by any means, just the easiest.

6. We can increase or decrease the stagger. This is never an acceptable way to tune the handling of your race car. For a defined radius of turn, there is an ideal stagger that will allow the car’s rear wheels to roll around that radius and not influence the direction the car travels from following that radius. Learn what stagger your track needs and use that.

The telltale way to know if your car’s setup is balanced is to read the average temperatures of the left side tires. Doing this tells us how much work those tires are doing. If the LF tire is cooler, then it is not doing enough work and we need to make the front more compliant, or softer, and possibly make the rear less compliant, or stiffer, until the left side tire temperatures match up.

Entry Problems

Once we have setup the car to be neutral in both handling and dynamical balance through the middle, we need to evaluate the entry handling. If our entry is without issues, meaning it is straight ahead, neither tight nor loose, and it needs no excess steering input beyond the normal transition from straight to left turn, then we are good to go.

If all of the alignment issues have been sorted out, there should never be entry problems, but there are influences that could affect entry stability and balance. Here are the top ones to consider.

1. Rear alignment is the number one cause of entry problems. The cause relates to either the misalignment of the rear tires or by the rear steering of the rear end. A car can become tight or loose on entry and that can translate to mid-turn problems. The truth is, you should have checked and corrected any rear-alignment problems long before you came to the track. Rear alignment and rear steer are not mid-turn tuning tools.

2. Shocks affect entry. Shock rates that restrict movement of one or more corners of the car can negatively affect entry. An LR tie-down shock, or one with excessive rebound control will help cure a tight-in condition by loosening the rear, but this is only a crutch.

The two corners most affected by the dynamics of corner entry are the LR corner and the RF corner. A RF shock that is stiff on compression can cause a tight condition on entry and a LR shock that is stiff in rebound can cause a loose condition on entry.

3. Brake bias changes affect corner entry. There is an ideal brake bias that will allow maximum braking of the front and rear set of tires based on the loads those tires carry. Different cars with different centers of gravity will require different brake bias.

Tune your brakes so that wheel lockup occurs simultaneously at the two ends of the car under heavy braking. We do not want the brake bias to influence entry handling characteristics. Never try to correct a tight car by increasing the rear brake bias or fix a loose-in car by increasing front brake bias.

4. Setup Changes to solve corner entry problems? We never want to make changes to our spring rates, sway bars, weight distribution, or MCs to try to solve entry problems. When we do that, we will certainly change our mid-turn handling in a negative way. We should have already tuned the car so the mid-turn handling was balanced correctly.

There is an exception to the above rule. We can initially plan out our spring selection so that our entry transition is best for the type of track we will be running. For flatter tracks, running even spring rates across the front or a softer RF spring rate as opposed to the LF spring rate will help the transition into the corner. It is best to make that choice before you go to the track so you won’t need to make changes after you tune the mid-turn.

Stiffer RF spring rates over the LF spring rate can help the transition into a high-banked track where the outside of the track rises up to form the high banking. In this case, the vertical forces are high at the RF on entry, and we need more spring rate at that corner to control those forces to limit excessive RF wheel travel.

Throttle modulation on entry can help solve problems associated with abrupt release of the throttle. If we quickly jump off the throttle and into the brakes, we can upset the car to the point where it affects our entry speed and stability. It can also cause us to slow too quickly and attain a slower speed than is necessary for the radius of the turn at that point.

Corner Exit Handling

Most of the time, solving the mid-turn handling will solve corner exit problems. If we were tight in the middle, we would most likely be tight off or tight-loose off. If we were loose through the middle, then we would be loose off.

The process of increasing mid-turn speeds means we have also increased our exit speeds, or the speed at which we begin to accelerate. This is a big deal, and the reason we spend so much time perfecting the mid-turn balances and trying to increase speed through that portion of the turns.

The way that some tracks are laid out contributes to corner exit problems. A flat track offers less grip than a banked track because we have less of the dynamic downforce created by the banking to help provide more overall grip. So, we need to enhance bite in other ways. The transitions in the track banking angle on higher-banked tracks may also contribute to exit woes.

Loose Off Condition

We can use Rear Steer to solve loose off problems. If we know we are good through the middle, then a loose off condition can be solved with the application of rear steer that happens only upon the application of power.

The most common way to create rear steer in cars equipped with the three link suspension is to increase the angle of the left trailing link, the front being higher than the rear. If we also decrease the anti-squat by decreasing the angle of the third link, when the car sits down on turn exit under acceleration, the LR wheel will be moved back creating rear steer.

We can tune the amount of rear steer by changing the angle of the LR link. This works very well and compensates for the rear tire drift caused by adding power. The rear tires will attain a new angle of attack to gain traction and if we cause rear steer, we immediately give the rear tires that angle of attack it needs without needing to step out.

Shock rates can temporarily increase the crossweight percentage on exit to tighten your car off the corners. If you run shocks with a stiffer compression rating on the LR corner than on the RR corner, then when the shocks move as the car squats coming off the corner under acceleration and while the loads transfer to the rear, then the LR corner will momentarily carry more load and the LR and RF will share that increased load.

Throttle Control

This is a learned art and will allow the rear tires to maintain their grip on the track surface and help to provide better acceleration. Once we lose grip in the rear, we must back off the throttle until we regain grip before we can continue to accelerate. By exercising throttle control, we may feel as if we are giving up performance, but in reality, we are providing the most acceleration possible.

Throttle control is defined as the modulation of the gas pedal through a range of motion, never moving quickly from one position to another, in order to keep the tires in contact with the track surface. The rate of change in throttle position must be altered depending on your position on the track and through the corner, so the driver must develop an educated foot.

Many dirt drivers report they never got past half-throttle over the course of an entire race in which they won. This means they were working from off-throttle to half and many points in between. The development of efficient throttle modulation is one of the most effective tools you can use to promote bite off the corners.

Final Words

The above suggestions are based on our belief that you have already solved the most critical issues facing your race car. Back at the shop, you have aligned it, checked, and corrected the MC design, checked for binding in the suspension, rebuilt the shocks, and done all of the other maintenance things we know we should.

The last thing to do is run the car. Teams that are conscious of the effects of all of the various changes and know basically how much affect each change has on the handling of the car will go through the process fairly quickly. If you’re just now learning these things, take good notes and concentrate on what is happening. Ask lots of questions of your driver, so you know exactly what changes to do and how much. And when you do get the car all dialed in, be sure to maintain that good setup.

Sources:

Afco Racing
(800) 632-2320
www.afcoracing.com

Allstar Performance
(269) 463-8000
www.allstarperformance.com

Capital Motorsports Warehouse
(800) 278-2692
www.cmwraceparts.com

Coleman Racing
(800) 221-1851
www.colemanracng.com

Day Motorsports
(800) 543-6238
www.daymotorsports.com

DRP Performance Products
(888) 399-6074
www.drpperformance.com

Integra Shocks and Springs
(800) 472-3464
www.integrashocksandsprings.com

Longacre Racing Products
(800) 423-3110
www.longacreracing.com

Mittler Brothers Machine
(800) 467-2464
www.mittlerbros.com

PitStopUSA
(866) 722-3432
www.pitstopusa.com

QA1
(800) 721-7761
www.qa1.net

Smileys Racing Products
(866) 959-7223
www.smileysracing.com

Speedway Motors
(855) 313-9175
www.speedwaymotors.com/

The post Tune Your Handling to Win appeared first on Hot Rod Network.

Over the years, track officials, sanctions and series have endeavored to make rules that will, in their opinion, save the racer money. Whether those rules actually do end up saving money for the racer is many times in question. Let’s take a look at why cost saving rules might be implemented and some instances when they really don’t save money.

There are several areas where the rules makers might want to enact rules that could make racing cheaper. This is a noble cause because the more expensive racing is, especially in the more stock classes, the fewer participants we see.

Tire rules are intended to save money week to week and can be simple, like only being allowed to buy only two new tires per week. Tracks may mandate cheaper or harder, more long lasting, tires, and/or make the Late Models run on cheaper, treaded tires such as we saw in Michigan at Berlin Raceway.

Motor rules are another way to save teams money. The crate motor rules are a prime example, but disallowing special cams, pistons, cranks, rods, heads and carburetors is a way of cutting engine costs that goes way back.

Sanctions are even now allowing more powerful built motors to run with the crate motors with a weight penalty and that saves the team money by them not being required to go out and buy a crate motor to run a crate class. That is all well and good unless a team buys a new expensive built motor to run a crate class because the weight penalty is not enough to offset the horsepower advantage. But that’s another story.

Then we get into the chassis and associated components part of cost saving. Basically we have the chassis itself and what is allowed for modifications and the components of the chassis like control arms, links, sway bars, springs, etc. Also regulated are the shocks, rear end, and brakes.

We are mostly talking about the stock classes when we get into the chassis part of cost saving, but recent changes in Late Model rules now allow teams to not have to abide by ride height rules anymore and the allowance of bump technology in NASCAR Late Models.

Let’s examine how chassis rules and shock rules might not help save money for the teams. First off, when a team decides to build a new Street Stock, there are rules in place for safety concerns that cost the team money. They must build a roll cage, install a racing seat, purchase seat belts, etc. Those things cost money and are labor intensive to do.

Then the rules makers disallow changes to the control arm mounts to “save you money” so they say. Hey, you’re already putting hundreds of hours into the build, what’s another couple of hours going to cost? When that thing gets bent up, it will take another bunch of hours repairing it with cutting and welding and new parts. Why not incorporate changes then when it won’t even cost more to do so? Oh, the rules don’t allow that.

Then there are the shocks. For many years, I have been with teams who had two dozen or more shocks in their trailer because the rules didn’t allow adjustable shocks. At $100 per shock, that is $2,400 in shocks. For the same money or less, the team could buy adjustable shocks and be able to fine tune their setup easily instead of having to remove and install different shocks all the time. This part of the rules has never made sense to anyone.

These are just two examples where rules intended to save money just do not accomplish that end. There are more but I have space restrictions here. The real cause of many cost saving rules might not be cost saving at all. It might have to do with other teams complaining that they cannot compete with the more innovative teams.

With the chassis, maybe the rules makers are trying to satiate the less innovative teams who either cannot or will not learn how to arrange their geometry to make the car better. They just want to keep everything equal like socialism. And the lame excuse given by the rules makers is “well, it’s the same for everybody”, like that makes it OK.

The “same for everybody” statement means that instead of having properly prepared race cars that handle well and are safe, we’ll just regulate them down to something less than a real race car. Then they won’t turn well, will run into each other often, and cost a lot of time and money to fix week in and week out. That is the hard cold reality of it.

Let’s stop bowing to the whimpering of less innovative teams who lack the desire to learn. If we keep the innovation in racing, it will grow the interest and the teams less inclined to get up to speed will have to become more inclined or get left behind. Why drag a whole sport down for the bottom 10% who might just be too lazy to put in the work required to run in the top 10%?

Listen, what I have just stated is the way it is. It might seem harsh or even cruel, but our world is designed that way. The smarter and stronger survive better. Every time we try to “equal it out”, things suffer and fall apart. Trust me, if I get flack about this piece, it will come from the lower 10% of performers.

If the complainers threaten to quit the sport, the chances are twice as many hard working and innovative teams will take their place and the sport will get better. But first we need to stop pandering to those who want equality. I’ve said it before and I will say it again, let my people go.

If you have comments or questions about this or anything racing related, send them to my email address: chassisrd@aol.com or mail can be sent to Circle Track, Senior Tech Editor, 1733 Alton Parkway, Suite 100, Irvine, CA.

Short Straight Axles

Bob,

I am building a Jr. Sprint for my daughter. They use a solid front axle. Would it be possible to use an independent front suspension? I was going to make shorter axle components and tie them into the frame rail, like a Mac Phearson strut. The coilover shock would mount to the top of the axle, closer to the wheel. I would add a small stabilizer bar to help prevent it from moving forwards and backwards.

I was wondering what would happen with bump steer, since the steering linkages would be longer than the axle. I just wanted to get your opinion if this would be a possibility. I am still checking to see if the rules require a solid front axle, which may make this a mute point.

Thanks,
Greg

Greg,
I think the bump steer would be the least of your problems. With the short straight axles, the wheel is locked in position as far as camber is concerned, with the axle. On a normal straight axle, the cambers do not change much at all and only from tire squash, i.e. load off the left front and load onto the right front as the car turns.

With what you have proposed, the movement of the chassis in dive and roll causes a lot of camber change to both front wheels with unpredictable results. I know that tires don’t like camber change, especially during corning. An asphalt application would work much better than using this on dirt I would imagine. But, if you could stabilize the chassis roll with a sway bar, you might have something that would work.

As to the bump steer, you’ll need to use a rack and pinion steering. You could make the axles long enough to put the inner mounts under the inner tie rod ends therefore making the radius for both the axle (actually a lower control arm) and the tie rod the same and eliminating bump steer.

You would need to modify the existing chassis anyhow, so why not put the mounts where you need them? Also, the link that locates the axles fore and aft needs to be mounted to the axle so that the axle will not rotate. Normally with straight axle cars, the links are wishbone shaped or two links, one above and one below the axle.

Control Arm Angles

I am a long time reader of your magazine. I read your track tech
monthly and have a few questions. I understand what Moment Center and Instant Center locations are. My question is how do I adjust the upper control arm angles?

I know how to set the bottom arm angles but the top is a little different. I was wondering if on the bushings the grips that are on them that catch on the shaft is how you set them but I can’t get my right front set at the right angle that I want it at.

I run an IMCA hobby stock on a 4/10-mile, high-banked dirt oval in Iowa and I am not needing an actual set up, I just need to know how to adjust the upper control arms. Any help would be very much appreciated.

Thanks,
Joe

Joe,
In most cases, we need to increase the upper control arm angles and/or decrease the lower control arm angles for better Moment Center location. For stock control arms, there are two ways to change the angles. You can cut the upper mounts and lower them thereby increasing the angle of the upper arms. This may or may not be legal. I know it is acceptable for some classes at some race tracks.

The other option is to install different ball joints. One type is the mono-ball, again maybe not allowable. This allows you to add spacers to adjust the arm angles for the upper arms as well as the lower arms. Then there is the low friction “stock” based ball joints where you can order different length shafts to change the arm angles that might be considered legal.

Both of these types may not be exactly “according to Hoyle” legal for your class. We never promote cheating, but we also realize that it is in the general interest of competition to make the cars handle better. Making these small changes, which cost very little to do, actually make for better all around racing.

If more promoters just could understand this principle, they just might loosen up the rules somewhat. In any event, you are doing the right thing by trying to improve your front end geometry.

Modified Balanced Setup

Bob,
I have been following your series on vehicle dynamics and achieving a balanced setup. Thank you for producing such excellent tech articles. I am the crew chief for one of three Super Modifieds on our team. We run on a variety of tracks from relatively flat one-miles to high banked ¼ miles all on asphalt.

We run around 68% left side weight, a solid front axle with panhard bar, and a live rear axle with panhard bar. Also, all four corners have different tire sizes. We will run up to 5-6 inches of stagger at times. With so many differences from a “stock” car, what difficulties or changes to procedure might I encounter? Our cars are light and powerful (2,000 lbs. and 650-700 HP), our corner speeds are already pretty high, but we’re always looking for improvement. Thank you in advance for your help.

Paul O.

Paul,
The basic principles we talk about are good for all stock cars meaning everything from mini-stockers like Legends or Dwarf cars up to and including the Cup cars. They are all race cars and all of them need setup that will help make all four tires work as much as possible within the limits of physics. The balanced setup, once achieved, makes that possible.

Supermods like yours have more even dynamic weight distribution left to right due to the high static left side weight distribution and therefore more available traction from the four tire contact patches. It also has a lower center of gravity which means less weight transfer and even more retained left side weight in the turns.

Having two straight axle suspensions is the biggest difference in your car vs. a stock or Late Model car. But that does not mean you cannot balance the setup. We still need to cause the car to be balanced in what each end of the car wants to do. So, we must balance the desired roll angles of the front and rear suspension. Evidence of having achieved this balance is having equal tire temperatures on each pair of tires on each side of the car. The left side tires should be equal in average temperatures as well as the right side tires.

The roll angles are influenced by the spring rates, the width of the springs (spring base), the moment center height and the weight supported by each axle. Speed is relative and if you can balance your car, it will be faster into and through the middle of the turns as well as having better bite off the corner, a definite necessity with all of that horsepower.

Adjust the heights of your panhard bars front and rear to balance the car. You might need to change the spring rates too if the balance is off by quite a bit. Softer springs will allow more roll angle and tighten that end of the car. If the left front is cooler than the left rear tire, lower the panhard bar or run softer springs.

Gear Selection

I have been looking through my old Circle Track magazines and I’m looking for something and was hoping you could answer my question. I was wondering if there is a way to find out what kind of RPM I will be running with a certain gear at a certain track. I hope you can help me out thanks.

Brian

Brian,
There is a formula for determining RPM from speed in Miles per Hour, if you know the speed, but no way to determine how your engine will pull the car down the straightaway for a particular track. There are some simulation software programs that might give you a reasonable estimate of RPM if you enter the correct engine and gear ratio information.

If your question relates to gear changes to affect a change in RPM, I can help you. Let’s say you are turning 6500 RPM at the end of the straightaway with a 5.26 gear and you want to turn 6800 RPM. You want to be able to calculate the gear that would get you close to the higher RPM. While it is no guarantee that the engine would exactly reach the RPM using this method, it will get you closer faster than trial and error swapping gears.

Divide the RPM you would like to turn by the current RPM. Then multiply that number times the current gear ratio and you will get the new gear ratio, in this case dividing 6800 by 6500 give us a number of 1.0462. That times 5.26 equals 5.50. Choose a gear as close as you can get to that with the available gear combinations. Because engines produce different horsepower and torque at different RPM, the car may or may not hit exactly 6800 RPM, but it will probably be close.

The post Saving Racers Money? appeared first on Hot Rod Network.