AX Tire Pressures

[RMP]

I upgraded from stock tires to Hankook RS-3 V2's last month and have a ran a few AX events with them in C-Street. Noticing some heavy shoulder wear on my front tires due to, I think, the minimal camber with OEM crash bolts (~1.3deg). I have been running 36psi hot up front and was wondering if that seems a bit low based on other peoples experiences. I would appreciate any advice regarding
setup.

Mods:
Strano Front Bar
OEM Crash Bolts

Alignment:
front:
-1.3 camber
0 toe
rear:
camber (I forget, but it was left at stock settings)
1/16 total toe in

215/45/17 Hankook RS-3 V2
Front: 36psi Hot
Rear: 33psi Hot

Lots of shoulder wear up front. The car feels pretty neutral with a slight tendency to push during corner entry and midcorner at these settings.

[knipple]

I have run 37 psi hot in the front, however I haven't autocrossed a C Street legal FR-S on good tires. I have been running 255/40/17 tires (Rivals and ZII*) on 17" X 9" wide (offset +35). When I was on stock suspension, I had -1 degree of camber in the front, now I am over -2 degrees in the front.

I would suggest you use tire chalk to determine how far onto the sidewall you are rolling and add air as required to stop the rolling.

[renfield90]

Different tire, but I run between 46-49 psi up front on Rivals depending on surface and conditions. I'm an oddball though and run higher than most other people on Rivals.

It's street class, you do what you gotta do to make it work.

[raul]

at least -3 camber in the front and -2 in the rear, along with 32 psi all around cold. Then bleed them as you run to keep them there. This is the consensus at least in our group of "fast guys" that run at nationals. These settings are for RS3s. If you start to get a bit of understeer, run the front half, to a full pound lower than the rear. However, don't expect tire pressures to completely fix deficiencies in your alignment. It simply won't happen. Also, is your ride height even all around? And where was it it measured from? Pinch weld? Ground to fender? Hub to Fender? The car needs a small amount of rake to make it work as well.

[RMP]

Originally Posted by raul

Also, is your ride height even all around? And where was it it measured from? Pinch weld? Ground to fender? Hub to Fender? The car needs a small amount of rake to make it work as well.

I'm currently running in CS so my camber is maxed out at around 1.3 using the crash bolts and I have to be at stock ride height.

I did some research on the SCCA forums and it seems that guys are recommending that the RS3's for 7" rims be run in the high 30's for cars that weigh about the same as ours. This was for the version 1 of the tire so I'm not sure if that is still valid for my version 2.

[wparsons]

If you can't adjust camber, your only option is to add some pressure and see if you can stop the tire from rolling over without losing grip.

The ideal solution is a lot more camber, but pressure might help to a point.

[Kido1986]

V1s and V2s have the same sidewalls so pressures would be close.

I think I ran 38 hot when I was running them. This will always happen with RS3s on a camber limited car, even at ideal pressures. RS3s have soft sidewalls. This made slaloming slower than I'd like but they sweep great. I switched to Dunlops which slalom better but a little less grip in a sweeper. The much stiffer sidewalls on the Z2 make direction changes lightning quick compared to RS3s when you lack camber. Plus, they oversize well unlike Hankook. Downside is they cost a decent bit more.

[raul]

If you're in C Street I would use the Z2, not the RS3 (sorry, failed to read where you mentioned in the OP you were in C Street.)

[mla163]

If you don't know at all, start at 40 psi and bleed down at 4 psi intervals to 28 psi. See how the car feels and check times.

The best way is to use a pyrometer.

[Laloosh]

I have 4-5 events on mine and they look great. 215/45/17 and I run them at 38f 36r hot.