Track Report ACR on Kumhos Inde

[Pappy]

Went to Inde with a group of Vipers for a private track day yesterday. Weather was cool (55 degrees) with no rain. I tried a new alignment with -2.5 degrees camber, 6.7 degrees caster, zero toe, and a rebound setting of 7. Ride height was at the recommended 4.0 in. front and 5.5 rear. I started with 30 lbs air pressure and had to bleed down from around 40 lbs to 33 lbs after each of the first two sessions (8-10 laps). After the second bleed, the air pressures stayed at 33 lbs the rest of the day. Front tire temps consistently showed 20 degrees cooler on the outside edges compared to the middle and inside, which were about equal. The car felt good with no notable push. Looking at the front tires and the tire temps, it appears I could go to 2.3 degrees of camber without hurting anything. The tires have 2400 miles on them with two track days, and they don't look too bad. They did not feel like they were giving up any grip. They should be good for at least one more track day. The rears look fine and are wearing evenly. When I first got the car the rears were at 1.7 degrees camber left and 2.0 right. After the first track day you could see more inside wear on the tire with 2.0 degrees camber, so that was too much.

Pappy

Viper Kumho 2.jpg

Viper Kumho 1.jpg

[99RT10]

How were your times in the car? Set any personal records?

[Pappy]

How were your times in the car? Set any personal records?

Didn't really get to time any laps, but they were aggressive, fairly competitive laps - a little slower than Arizona Vipers ACR with 335/345 Hoosiers and more experience on this track, but that was to be expected. If the track was a little warmer I suspect there was room for 3-4 seconds improvement in my times. I will have video and timing capability the next time out.

Pappy

[stradman]

What rear wing are you running?

[Pappy]

What rear wing are you running?

Standard ACR wing still set on "2" high down force.

Pappy

[stradman]

Standard ACR wing still set on "2" high down force.

Pappy

Its interesting how there are quite a few variances with the camber/rear wing/caster. Of course we all want to try to save as much of the front tires as possible and it seems you feel maybe at 2.5 or lower camber could work and keep handling tidy. I'm off for a geo setup/corner balancing on my ACR-E tomorrow and will discuss with the guys there about all the options and let you all know what we figure too..

[Arizona Vipers]

Man we've got some math geniuses on here.