Originally Posted by
cwoods34
Mind my asking why you changed rear tires? And are these VTA tires?
Yes VTA tires. I had brought several sets, new, broken in, and used. The set I had on was fairly new, but after a wall collision and in combination with the traction coming up, part of my glue job was failing, and the tire had pulled away from the rim over about an inch. Replaced the rears with a set that was almost the same, broken in, but with 2 less runs on them. I assumed that the issue was somehow with the tires. Reglued up the first one, ran those in the next heat (the ones that worked all Friday and the first part of Saturday) and same issue, violent stepping out of the back end. Had it in particular in the sweeper, the corner coming onto the straight, and the pair of corners that made of the tail or the sweeper. The slower speed corners were not an issue unless I took a bad line in and got hard on the throttle. Otherwise, would maintain speed, roll the corner and ease back into the throttle and was fine.
I had been running 2.5 blocks for both on the front end with a 0.5mm spacer on each wheel (for clearance around the spindles). This gave me a wider front stance which had worked well with lower traction, but had a lot more bite as traction came up. I changed to a pair of 1.0 blocks, along with adding 1mm of shims to both rear blocks, and the rear front block. The front front block I added 0.5mm to. I also removed .5mm of spacers from the inner and outer rod ends on the rear. I was told this would help settle the car into the corner less abrubtly and make it a bit lazier. The idea being that the weight transfer would be less and if the back end lost traction, it would be slower to come around. Raising the front shocks, laying down the rear did more of the same, less front bite, lazier rear end. Changed the rear bar from 1.4 to 1.2, and everything magically started working. Rear end rotated nicely, but stayed glued when I needed it to. I think I could probably get it handling a little more accurate so that it would cut the corners more then it does now, but I was out of time. The car hooked up in the main, and going back to the home track and everything will be changing again.
Ended up running the main on the rear tire set that I started the weekend on as well.