Observations and Lessons from Bristol Test Day

The first test day for the upcoming Short Track U.S. Nationals presented by Vore’s Welding & Steel was on Saturday, April 29^th. We attended and made what I think are valuable observations. I had a lot of anticipation for this race and presented a previous piece on the uniqueness of Bristol hoping to help any teams who might decide to race here.

The cars are all lined up on the front stretch at Bristol Motor Speedway. There were approximately 50 cars that took part in the test on April 29th. There were Super Late Models, Pro Lates, Late Model Stock Cars, Street Stocks, Modified and Compacts.

As you recall, the banking at Bristol is progressive starting at about 24 degrees and going up to 26 degrees in the middle groove to about 28 degrees at the top. The Cup race was run this past Monday due to a rainout on Sunday and the track had applied a sticky substance to the lower groove. That was still present and caused many to run the bottom starting out.

I stayed around for the early running of this test and had to leave in the early afternoon to get back home from an extended trip to Mooresville before coming here. What I saw was plenty to further aid in preparation for anyone deciding to run these races. And I can tell you that most of the teams were well prepared and might I say some were over-prepared and that’s OK.

The speeds the various classes ran were much higher than would be seen at the local tracks they usually run on. Here is the rundown of the top speeds I measured: Super LM 129.01 mph, Pro LM 127.00 mph, Late Model Stock Cars 122.75 mph, Modifieds 114.70 mph, Street Stocks 108.18 mph and Compacts 94.82 mph. Compare that to the top speeds at New Smyrna Speedway of around 105 mph and Bristol is over 24 mph faster.

Starting off, the Super Late Models ran the first practice and Steve Wallace showed his experience here by getting up to speed right away. The first casualty came soon after as Dave Russell got loose coming off turn four and tagged the wall with the rear and the front of his car. He said he had a pre-loaded right rear spring, something that can work well at lower banked tracks, but not here.

The first incident involved the number 93 car driven by Dave Russell. Here is the before shot. He had installed a pre-loaded softer right rear spring and that is not recommended at Bristol. The softer spring, once the travel was reached, caused a tight/loose condition that sent him rear end first into the wall.

This is the after photo. First the rear hits, then the front on most of the cars that contact the wall here. Once it starts going, it’s very hard to avoid contact. About five other cars suffered the same consequences.

The Pro Late models, Late Model Stock Cars and Modifieds all ran relatively without incident. We noticed that some cars were loose with the rear drifting out, some has too little left front camber and some of the Modifieds looked like they had Ackermann in their front ends that is sure to slow them down. Some of the cars eventually moved up a groove, but mostly stayed on the bottom.

In a previous tire test, low tire pressures caused a car to contact the wall, so Hoosier set mandatory tire pressures for the late models of 22psi left sides and 32psi on the right sides. Several Hoosier tech officials were seen taking tire temperatures and pressures at random. The teams had been told in the drivers meeting to expect that and to cooperate.

For a more detailed analysis, refer to the photos I took. All in all I was impressed with the preparation and the speeds these drivers were able to attain with most of them coming here as “rookies” at Bristol. For any of them who had raced at Winchester Speedway, it was easy to get used to this track since Winchester has somewhere around 30 degrees of banking.

For those who are waiting to test in the second day of scheduled practice slated for May 13^th, just remember to spring up 2.5 to 3.0 times the spring rate you are used to running for conventional setups. For those who run bumps, let your ride springs take 80-90% of the force and the bumps only 10-20% for this track.

Note the high ride height on this car. This is typical for Bristol where the high mechanical downforce results in a lot of spring travel. You must spring up here, either using stiff ride springs, or stiffer ride springs along with the bumps. The total force on each wheel is about 2.5-3.0 times what you normally see.

Tires and tire pressures were a high concern among Hoosier officials. Here we see one talking to a crew chief going over the results of temperature and pressure readings. The crews were told in the drives meeting to expect inspections and to cooperate.

Be sure to prepare your car for the additional travel and set your cambers accordingly. Check for Ackermann and even if it works for your normal bullring track, with the higher speeds and geometrically longer turns, you won’t need the added toe.

Your rear springs should be normal springs like on conventional setups even if you run pre-load or bumps in the rear. Those trick setups will get you in a lot of trouble at Bristol. The rates of the rear springs should be at least double your normal average rate with less spring split.

So there it is, a successful tests and a lot of teams who are better prepared going forward to race day. Again, this will be an exciting event that we hope will catch on with the teams and fans of short track racing. If you plan on competing here, have fun, go fast and keep turning left no matter what.

The continual high speeds take many crews by surprise and gear changes were common. With those high speeds, the engine will run out of RPM long before you expect it. It might be better to be geared too high than too low starting out to save the engine.

This was one of many that were hanging out the rear of the car. Loose was the order of the day and some teams got away with it and others did not. This could be a result of rear steer, or just a free setup. The bottom groove was the only one that produced good lap times.

This was the fastest Street Stock at Bristol and if looks make you fast, that’s what did it. With such a high profile show coming up, the teams stepped up and prepared their cars like Cup cars. This one looks as great as it ran.