On race day, I got there pretty early. The track would probably keep changing, so I wanted to make at least a couple practice runs to see where the track was headed. The club decided not to re spray the VHT, so I assumed that the traction would continue to diminish. Fast lap on Saturday was at 19.1, and I don't think we came within half a second of that Sunday.
I switched to black front springs from gold after the first run I made, mostly because they calmed the front end down a bit, and actually added some turn in. That may sound contradictory, but I think the car was diving around, but didn't turn in positively. The car stayed flatter with black springs. In addition, I added a shim on the front axles, I think a .5mm. Again, this was just to stabilize the car a bit.
The goal on the day was really to just get the car dialed in with small changes. Saturday, I was able to get the major stuff out of the way, so here it was just small stuff. Mostly, this was front ride height, shims on the kingpin, and height on the rear shock, not necessarily in that order. After a few practices, I started to raise the front end up again. The car was not getting the forward traction it needed, and raking the car back just seems to get the forward bite back into it. I had taken all the posts out of the upper deck as well, so the car was able to flex a ton.
The front end actually wound up where it started, raised front ride height and an almost flat upper front arm. I had raised the arms at the kingpin by 1mm on Saturday, but by this time it was too much. After i brought the arm back down, the car still had plenty of steering, but I had more confidence to drive it in traffic.
The rear ball on the shock was actually key to how the car worked. I was amazed at how big of an effect that had on the traction of the car. I felt like soft rears and kit fronts with stock inserts were the tire to run, and there was a sharp difference between a raised shock and lowered shock. Really, that tire combo would have been hard to use without raising the shock up. .
Speaking of the tires, I ran the soft rear and kits in the first round, and I was able to qualify first. At the same time, I had to stay up on the wheel big time, as it was sensitive. For the second round, I switched to a set of kit fronts with a sedan insert in the front, but the car pushed at first and never picked up any steering. I had hoped it would balance the car out, and maybe even be better at the end of the race. I tend to think that to be fast the car just has to be a bit on the edge unless the bite is out of control.
For the main, the kit fronts with stock inserts went back on the car. I was starting second to Bruce "Doc" Hickman, who had been fast all weekend. The track continued to go away, so I figured I would just try to keep it close until the tires warmed up. Right behind us was Rocky, who was racing F1 for the first time, but he had shown to be a good driver who was still dialing in his "rent-a-ride".
When the tone went off, I was able to keep pace with Bruce. We were able to break away from the pack a bit, but both our cars seemed to be a bit slippery at first. As far as I could tell, he had a slight advantage in the infield, and my car got onto the straight and through the sweeper better. We went a round a few laps until we got into traffic, and bumped a bit, and I backed off so Bruce could maintain his position. As all this was happening, Rocky was able to gain ground and come back into touch with us. I tried to stay close in traffic, and at one point Bruce touched a corner while we were getting around another car. I was able to get into first at this point. As Rocky came up on Bruce, I was able build up a decent gap getting onto and off of the straight until I could relax a bit. At that point, it was going to be hard to make up enough ground in the time left to catch me, so I was able to take the win with a little gap.
I'll try to get the setup sheet tomorrow.
Showing posts with label TCS race report F104. Show all posts
Showing posts with label TCS race report F104. Show all posts
Monday, June 6, 2011
Saturday, June 4, 2011
Memphis pre TCS club race
Kind of a crazy day at the Saturday club race for the Memphis TCS. I got there pretty early in the morning, and ran a bit on the track, which had not really been prepared too much. After about 2 packs, they wound up spraying the track with VHT cut with methanol. Instantly, we had very high traction.
Immediately, the order of the day changed from finding stability to getting the car steering. I wound up doing some things I would not have predicted. I kept the 3.5mm offset steering blocks. I tried the stock block, but it didn't seem to help much on the tight parts of the track, which were many, and almost had less steering in other parts. This is very different from carpet, but perhaps it's a function of the rubber tires. I feel like the the steering block is a big adjustment, where you work other things around that decision. So I started to raise the upper arms at the steering knuckle. The car was very stuck so this actually was not as bad as I thought it might be.
I did also try more static camber, but it almost seemed to be riding on the edge of the tire. I don't know if that was more a function of the tire setup, but it was not turning in the way I wanted. Going back to 1.0 camber, the car turned in better. Angling the upper arm as I did got enough camber into the front end in roll, so keeping more tire on the ground was fine.
One more note on the front end, I did not have any grease on the kingpin to start the day, and one set of tires wound up really making the car hop. So I went right to 120K diff oil. Somehow, I didn't think it would make a huge difference, but in reality not only did it make a huge difference in the hopping, the car was MUCH more responsive. Sometimes, on carpet, I thought some over responsiveness was coming from the damper plate, but I now think that over dampening the kingpins is a lot of the reason for the twitchiness.
The upper deck was also part of the fun. I wasn't sure if the added traction of the VHT would make a big difference in what I needed to do as far as stiffening the chassis. Starting with only the pivot post connecting the upper deck, I made some changes, but that is where I ended. I tried 2 posts in both the forward and middle positions. Both provided a more locked in feeling, but they took away some steering, especially on turn in. The other part is that the more flexible chassis hooks the car up in general, especially in rear traction. As the day went on, traction seemed to fade a bit, so the most flexible option was still the best.
The rear shock height was also way more sensitive than I expected. For much of the day, I wasn't quite sure what to do to get the car to keep turning off the corner. I tried a stiffer spring, which was ok, but not quite what I was looking for. I took only 1mm off of the rear ballstud for the shock, leveling it a bit. This made the car very responsive, and almost loose! The next run I added the spacer back, along with an additional 0.5mm and this went right back toward a push on power. This actually made it possible to use different sets of tires based on how much rear bite the car had on power. I did not change the front ballstud at all, and I am curious if it is as sensitive as the rear ball stud is.
The little 1800 pack also came out for this race, with as much traction as there was. I ran it until about mid afternoon, when traction seemed to fade a bit. The 1800 is perfect when traction is high, since it is obviously faster even to the naked eye. I had a guy ask me if I had a brushless motor in the car, lol. However, as the day wore on, I went to an Orion 3200 to provide some more mass, and that turned out to be the best choice in the later afternoon. The track had quite a few 180s and slow sections, so the stability and forward traction were much more valuable than overall speed.
For tires, I started with a set of Option soft rears and kit fronts, with stock inserts. The tires actually were great. Later I tried the same type of tires with a 26mm sedan insert, and the car actually locked down quite a bit, and started to push. I was surprised, but even with the high air temps (99* F) softer inserts were better. Later, on advisement from my buddy Jay, I tried a set of tire with no insert at all. This can actually be a good option when the temperature is high since the tire cools better. I did notice that I ran better in the last half of the race. At the same time, as the day wore on and traction faded a bit, these tires pushed just a bit. The stock inserts were just a bit better, especially on steering. The thing you had to be careful of with the stock insert was roasting the tires at the end of the race.
The car was definitely really good, so tomorrow should be very exciting...........
Immediately, the order of the day changed from finding stability to getting the car steering. I wound up doing some things I would not have predicted. I kept the 3.5mm offset steering blocks. I tried the stock block, but it didn't seem to help much on the tight parts of the track, which were many, and almost had less steering in other parts. This is very different from carpet, but perhaps it's a function of the rubber tires. I feel like the the steering block is a big adjustment, where you work other things around that decision. So I started to raise the upper arms at the steering knuckle. The car was very stuck so this actually was not as bad as I thought it might be.
I did also try more static camber, but it almost seemed to be riding on the edge of the tire. I don't know if that was more a function of the tire setup, but it was not turning in the way I wanted. Going back to 1.0 camber, the car turned in better. Angling the upper arm as I did got enough camber into the front end in roll, so keeping more tire on the ground was fine.
One more note on the front end, I did not have any grease on the kingpin to start the day, and one set of tires wound up really making the car hop. So I went right to 120K diff oil. Somehow, I didn't think it would make a huge difference, but in reality not only did it make a huge difference in the hopping, the car was MUCH more responsive. Sometimes, on carpet, I thought some over responsiveness was coming from the damper plate, but I now think that over dampening the kingpins is a lot of the reason for the twitchiness.
The upper deck was also part of the fun. I wasn't sure if the added traction of the VHT would make a big difference in what I needed to do as far as stiffening the chassis. Starting with only the pivot post connecting the upper deck, I made some changes, but that is where I ended. I tried 2 posts in both the forward and middle positions. Both provided a more locked in feeling, but they took away some steering, especially on turn in. The other part is that the more flexible chassis hooks the car up in general, especially in rear traction. As the day went on, traction seemed to fade a bit, so the most flexible option was still the best.
The rear shock height was also way more sensitive than I expected. For much of the day, I wasn't quite sure what to do to get the car to keep turning off the corner. I tried a stiffer spring, which was ok, but not quite what I was looking for. I took only 1mm off of the rear ballstud for the shock, leveling it a bit. This made the car very responsive, and almost loose! The next run I added the spacer back, along with an additional 0.5mm and this went right back toward a push on power. This actually made it possible to use different sets of tires based on how much rear bite the car had on power. I did not change the front ballstud at all, and I am curious if it is as sensitive as the rear ball stud is.
The little 1800 pack also came out for this race, with as much traction as there was. I ran it until about mid afternoon, when traction seemed to fade a bit. The 1800 is perfect when traction is high, since it is obviously faster even to the naked eye. I had a guy ask me if I had a brushless motor in the car, lol. However, as the day wore on, I went to an Orion 3200 to provide some more mass, and that turned out to be the best choice in the later afternoon. The track had quite a few 180s and slow sections, so the stability and forward traction were much more valuable than overall speed.
For tires, I started with a set of Option soft rears and kit fronts, with stock inserts. The tires actually were great. Later I tried the same type of tires with a 26mm sedan insert, and the car actually locked down quite a bit, and started to push. I was surprised, but even with the high air temps (99* F) softer inserts were better. Later, on advisement from my buddy Jay, I tried a set of tire with no insert at all. This can actually be a good option when the temperature is high since the tire cools better. I did notice that I ran better in the last half of the race. At the same time, as the day wore on and traction faded a bit, these tires pushed just a bit. The stock inserts were just a bit better, especially on steering. The thing you had to be careful of with the stock insert was roasting the tires at the end of the race.
The car was definitely really good, so tomorrow should be very exciting...........
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