The UFR tow rig sits in front of the Automotive Technology Center, across the river from B
The UFR team finished construction of the new Super Late Model car, so I made the trip up to Beloit to help them prepare for the first race of the season on May 9th. We have promised to keep you informed as to the progress of the car and how we would prepare it and set it up. The following is a detailed account of that process.
When I arrived, I quickly drove to Madison International Speedway to watch the first test of the new car on the Wednesday before the first Friday race. The crew had been pushed to finish the car and had installed a setup from last year just to shake the car down and make sure all of the systems were functioning. I wasn't much concerned at this point in how it handled. We would be making wholesale changes soon.
Once we had the car back at the race shop in Beloit, I outlined the process for evaluating the car and setting it up. I let Pete Raskovic and the crew chief know that we would be putting in a whole new setup, but first things first. I would need to do a complete evaluation of the car before moving on.
The shop area where the car is weighed and set up had been marked for the scale locations
The following is the exact process I used and in the order presented to make sure the car was aligned and adjusted properly.
The entire crew of students, along with Pete and myself, went over the car and looked for any possible conflicts with clearance, binding, or other mechanical problems that could have a negative affect on our setup. We found shocks that were not spaced properly, a tie rod end at the spindle that did not have the spacer installed on top, and a Panhard bar mount on the axle tube that we would need to change for clearance (more on that later).
Clearance problems and mechanical binding can ruin an otherwise great setup. If one shock mount is not spaced properly or the mount is not built for the design of the top of the shock, then binding may occur that will stiffen that corner and completely change the handling. We found several areas of concern and corrected them before moving on.
The rear shocks were mounted with the tops to the rear causing an angle of about 18-20 deg
We now checked all of the steering functions. These included:
1. Bumpsteer - Our bumpsteer was horrible. Each side bumped out over 0.100-inch in one inch of travel. We mounted a single dial bumpsteer gauge and proceeded to correct the tie rod alignment until we got zero bumpsteer in 2 inches of travel with the RF in bump and the LF in rebound. The next inch showed less than 0.004-inch steer.
2. Ackermann - We checked our Ackermann and found that it was set to provide an additional 0.210 of toe in approximately eight degrees of steering. This was more than I wanted, so we adjusted the left steering arm to full length and reduced that to around 0.065-inch of added toe. This was the least we could get and at this track would be acceptable. What we didn't want was 0.500-inch or more of added toe that comes from a degree or more of Ackermann.
3. Rear Steer - The rear trailing arm angles were set to LR 1.0 degree up hill to the front and the RR at 2.0 degrees up to the front. These angles would provide nearly zero rear steer with the amount of roll we would be getting.
Bumpsteer was an issue. When we initially checked it, we found over 0.100-inch of toe-out
1. Set front toe at 1/8-inch out - This was done after we had centered the steering rack and locked the steering shaft so that the wheels would be pointed straight ahead with the steering rack centered.
2. Check rear square - The rearend was set according to the squaring tabs installed by Lefthander Chassis. Even though these are usually correct, I always double check the square. In this car, the rearend was indeed square.
3. Check right side tire alignment - The right side tires were aligned at the hub height. I prefer alignment at the contact patches and we did re-align them later on.
4. Pinion / driveshaft - We did not have a chance to check this with angle finders, but a visual inspection told me we were close. The angles were less than 4 degrees and opposite at the pinion versus the transmission. We will do a detailed analysis of the alignment later.
The Ackermann effect was more than what we wanted in this car. It measured 0.210-inch of a
5. Caster and Camber check - Our caster split was LF = 1.0 and RF = 4.0 degrees. This is more than I think we need, but for now we will keep these settings.
The initial cambers were: LF = 5.8 degrees and the RF = (-) 2.7 degrees. We changed these numbers to LF = 3.75 and RF = (-) 3.25 degrees. These are based on our anticipated dive and roll for the setup we intend to use.
1. The front anti-dive was approximately 5 degrees on the RF upper control arm angle from a side view and zero degrees in the left upper control arm. This is fairly standard anti-dive split whereas many teams are resorting to pro-dive on the left front. We felt we did not need any special effects with our setup.
2. The anti-squat effect from third link angle was set at around 8 degrees of third link angle and sufficient for our car.
Initially we were faced with a Panhard bar situation where we could not move the left end down to much less than 11 inches due to conflict with the under-slung frame rail. We also had a small 11/8-inch sway bar installed. This produced a high degree of roll tendency in the front and a much smaller amount in the rear. We decided to make some changes. Here are the starting setup numbers and the ones we changed to:
Our anti-dive in the front suspension was set with about 5 degrees of upper control arm si
The Original Setup: Springs RF = 250, LF = 250, LR = 185, RR = 225. Panhard bar height from the ground - Left = 11 inches, right = 12 inches. Cross weight = 60.3 percent (with 50.2 rear percent), sway bar size = 1.125-inch outer diameter with a .75-inch inside diameter.
The New Setup: Springs RF = 250, LF = 250, LR = 200, RR = 200. Panhard bar height from the ground - left = 9 inches, right = 10.5 inches. Cross weight = 53.0 percent, 1.375-inch hollow sway bar diameter with 1-inch inside diameter. NOTE: Keep in mind this is a setup for this car only. Your car will have differences in several areas, particularly weight distribution. Please don't just throw this in your car and expect it to work.
We installed a new panhard bar mount on the rear axle tubing that put the left end of the panhard bar to the right of the left frame rail. This allowed us to move the mount down past the frame rail and get our left height of 9 inches.
The Ohlins double adjustable shocks we used were set to neutral (mid-range) for compression at the front and rears. For rebound, we added three clicks to the fronts and took three clicks out of the LR shock. This was done to let that corner rebound quicker to accommodate the abnormal transition off Turn 4. The RR corner rebound was set to neutral.
A former student, Tequad Tillman, stopped by to help out and look over the car. He was one
Now that we had established our spring rates and weight distribution, it was time to set the car on the scales and re-set ride heights and wheel weights. This is a process that takes some time, but once all of the other parameters have been established, it would be the final routine before taking to the track.
Our next job was to load the trailer the next day and head off to the track for the first race of the season at Madison International Speedway, an ASA member track in the Midwest. The student's permission slips from their parents were turned in, the car was loaded, and we were ready.
Once at the track, last minute preparations were made and it was discovered that some bolts that needed it were not safety wired. Next the students were shown how to select the tires, air them up, and set the starting pressures.
Dan displays one of his good luck charms (he has several - we won't go into that here) he
Pete had a list he called the "Team Roster/Duties" that stated in bold print, "DO NOT DEVIATE FROM PLAN." Each member of the crew, including myself, had been assigned a job to do. I looked up and down pit lane and no team had any more order and enthusiasm than this young group.
The crew chief Pete selected for the season was Jerry Perryman, a veteran at Madison. I watched him work with the kids at the shop and at the track and I knew from his patience and understanding ways with these rookies that Pete had made a good choice. Jerry was helped in the spotter's box by his brother, Jeremy, and also brought along his friend and veteran mechanic, Joe Koneski.
We had one hour to practice the car and make any adjustment that might be needed. The first time out, we turned about eight laps and came in to check everything out and take tire pressures and tire temps. The LF tire showed about 25 degrees cooler than the LR tire. This indicated a tight setup and we moved the left side of the Panhard bar up a 1/2-inch. Remember that our split was 11/2-inch and this closed the split to 1-inch.
I think I heard somewhere that good luck happens when proper preparation meets opportunity
Dan took the car back out and we ran about ten laps. When we again checked the tire temps, we had gained heat in the LF, but we were still about 15 degrees cooler than the LR. We moved the Panhard bar up another 1/4-inch at both ends and sent him back out for the final session and ran as many laps as we could.
This last change evened up the left side tire temperatures and produced more heat in all of the tires than we had seen before. This gave us a good opportunity to check cambers in the front. Surprisingly, both the LF and RF showed more even temperatures across the tread, so no changes were made to the cambers.
The team had been running a light 11/8-inch diameter sway bar and it produced a lot of rol
We did initially show a cool outside temperature at the RF, but this was a result of the crewmember taking a temperature too far out on the very edge of the tire and not penetrating the rubber sufficiently. Once this was corrected and the student tutored on correct placement and penetration of the probe, the temps looked good.
The most important data we got was from the driver. After the last series of laps of practice, he said over the radio, "No more changes, I like the car just the way it is." No one had ever remembered him saying that before they told me. I think by going through the car and checking everything that could affect the setup and making it all right produced a racecar that was easy to tune for dynamic balance.
The reason why we needed to make the adjustments we did was because even with the computer tools we have today, there are still numbers that are hard to quantify. Every car has a different center of gravity height that is very hard to measure. Besides, we still haven't had the opportunity to play with different shock settings. There was one more thing I failed to consider.
Once at the track, the car was gone over once again and prepped for practice. We only had
The newer Lefthander rear shock mounts at the top are moved to the rear so the shocks are tilted to the rear to increase the length of the spring base. This is something Wayne Lensing, the owner of Lefthander, and I talked about and I completely understand his reasoning. The end result of that is a dynamic reduction in the spring rate the car actually feels compared to the installed spring rate. The spring was angled back about 18 degrees.
To do the calculations to find the dynamic rate, you take the cosine of the angle and square it before multiplying the result times the spring rate. The cosine of 20 degrees is 0.9511 and that squared is 0.9045. Multiplying that number times the 200 pound per inch spring rate gives us a dynamic rate of 180.9 ppi.
So, the 200ppi springs I installed basically felt to the car like a pair of 180s. That is a significant difference that would necessitate raising the Panhard bar in order to compensate. Remember that springs that are installed at an angle to the motion of the chassis have a softer feel to the car, so take that into account when choosing spring rates.
Each crewmember had a specific role to play that was well defined on a sheet that was circ
We were all set for qualifying. Pete had purchased just one set of new tires for this race and we had run them in the last practice putting about 20 laps on them. This would be a disadvantage in qualifying because all of the other top teams had sticker tires on. That was OK because this was intended to be a shakedown run and if all went well, we should be able to make up the difference in the race.
We qualified Sixth and the invert put us in the second row inside. On the start, everyone went outside and we got pinched down low for the first two laps until we could get back in line in about eighth place. Dan quickly passed two cars in the next three laps and set his sights on the lead pack. He was clearly closing on them at a rate of about a half a car length a lap. With twenty laps to go coming off of Turn 2, alone, the car suddenly snapped loose and spun. Dan said over the radio it felt like he had been hit, but no one was near him. We suspected a part failure.
Upon inspection back in the pits, we found we had sheared the left outside axle spline. We isolated the problem and debriefed the driver. From the look of the car on the track and the comments from the driver, we felt we had a real contender. The crew did a great job in all of the tasks and this just served to show that this high school program is all it was intended to be and more. These kids are genuinely excited and dedicated.
The next race would be two weeks later, and the next race Rob and I will be attending is the July 11th race. Until then we will be in contact with Pete and the crew to monitor their progress and help them in any way we can. Any changes to the car's setup or race routine will also be reported.
After the first practice we noticed that the LF tire was cooler than the LR. This indicate
We wanted to start this project with a standard setup with normal shock rates and no frills or tricks up our sleeves. We really wanted to prove that by doing all of the procedures we teach in the pages of CIRCLE TRACK correctly and putting together a solid package, you can experience good performance without tricking up the chassis. I think this first outing proved that to be true.
The car was very neutral in the turns, it was as fast or faster than any other car there and it came off the corners like Jack the bear - anyone remember that clich? I asked Jerry, the crew chief, if he ever thought a pair of 250s up front and a pair of 200s in the rear would work and he said, "Never in a million years." But, it did. And that is the point. We intend to be competitive with this and other various setups because we will keep the car aligned, we will maintain the corner weights and make small tuning adjustments where necessary, but no large scale modifications to the setup. Yes, in due time we will be changing the setup to a softer set of front springs and a larger RR spring coupled with a larger sway bar. Do we think the car will get faster? No, but we will try it and report exactly what we find. Stay tuned.
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