ericstanley

I'm running stock sized PS2s on stock rims on a mostly stock (intake and exhaust) 02 Z06 with stock alignment settings (lowered on factory bolts, alignment done after lowering) for autocross. I've been in 2 practice events (one of them today). Today I had nearly no rear grip the whole time. I tried to stay focused on driver errors and which line to run, but I couldn't help but notice the lack of rear grip most of the day. I ran 40psi in all 4. Any words of wisdom (other than r compound tires... that will happen eventually, but not now)? FWIW, I tried all 3 A/H settings, with OFF yielding the best results.

Thanks,

Eric

ZBRA

I've had great results with my blue C4 using old Michelin Pilot Sports and my C5 using stock Z06 Goodyear Supercar tires. Both worked great, and I can't really say which one was better.

Z06Fix

First thing I would do is drop those pressures. I'm running Kumho MX's and have found that 33psi front and 32psi rear seems to be about the sweet spot. Enough pressure to keep them from rolling, but low enough to get heat in them pretty quick. Driving these cars on street tires is not easy by any means. It will teach you throttle control very fast

ericstanley

I'll try that next time. My biggest worry is rolling on the rim... I like my shinies and I don't want to kill them...

NO KIDDING!!

Bimota Guy

Do some testing with lower pressures (drop in 2-3 pound increments) by putting a few dots of white liquid shoe polish at the edges of the tires (where trear meets sidewall.) When you get down to where you roll off the edges (unless you are driving poorly), then bump it back up a couple of pounds. Not all street tires (nor R compounds) will work at the same pressures. And many street tires have such (relatively) soft sidewalls you will need high pressures.

ericstanley

Sounds like good info. Thanks!

Bill Dearborn

I found that white shoe polish doesn't really work on the wide tires that come on these cars. To get rollover you have to run some really low pressures. One of the posts above mentioned 32 front and 30 rear as starting places and I think you will be surprised how much that will improve the car.

I have run pressures on my Z with GY SCs and Firestone Wide Ovals as low as 28 front and 26 rear depending on the course layout and course condition.

Bill

Red5

Believe it or not I've had good luck using Summitomo tires. I run 315s all the way around and they grip pretty well for a street tire. And at $85.00/tire it's hard to go wrong. These tires worked well both wet and dry.
I switched from MX's, these seem to offer more grip.

Definately lower your air pressure to 32-33 or so.