Autox and tire discussion

[Norm Peterson]

Originally Posted by JDP Motorsports

I'm running the Michelin PSS 295/35R20 in the front and the 315/35R20 in the rear. The tires work very well and I am pleased with the overall performance. I have had issues with the outer edge pealing and chunking which frankly sucks after 1 event...

Originally Posted by So Cal Camaro

The edges on the PSS are an issue, mine wear out that side too fast...but from what I have seen on cars, the Rival's aren't any better...in fact given the weight . . .

Front tires? Rear tires? Both?

The Michelin PSS is on my short list for rack time tires and I'm wondering if they have some sensitivity to camber or wheel width that I ought to be aware of (and consider doing something about before shelling out $$$$). 285/35's on a ~300 HP 3500# car isn't all that much better than 295/35's on a 3800# car or 315/35's with 400+ HP.


Norm

[Cuda7050]

Originally Posted by Norm Peterson

Front tires? Rear tires? Both?

The Michelin PSS is on my short list for rack time tires and I'm wondering if they have some sensitivity to camber or wheel width that I ought to be aware of (and consider doing something about before shelling out $$$$). 285/35's on a ~300 HP 3500# car isn't all that much better than 295/35's on a 3800# car or 315/35's with 400+ HP.


Norm

I had the same problems with my Michelins 275 PSS's at Thunderhill. The problem on the outside of the tire was much worse on the fronts, but was still noticeable on the rears. My camber was basically -1.0 front and -0.8 rear. I am going to -1.5 front and -1 rear for my next HPDE in April. I don't think its a problem for autocross, just on longer 20 minute track sessions where heat is more of a problem.

[Norm Peterson]

Cuda - are you still on the OE SS wheels? 275/35-20's, I assume.

I'm with you on the relative effect of track session time vs autocross run times.

Thanks for the camber data points.


Norm

[SPCBA]

Neeeeeds more - camber

[Norm Peterson]

Originally Posted by SPCBA

Neeeeeds more - camber

In Cuda's case, yes.

I don't know what cambers JDP or So Cal are running with, though, and there is still the possible influence of wheel width relative to tire width for Cuda.


Norm

[NJ Drive]

Originally Posted by So Cal Camaro

The edges on the PSS are an issue, mine wear out that side too fast...but from what I have seen on cars, the Rival's aren't any better...in fact given the weight of our Camaro's, none of the tires I have tried fair well on the outer edges, oddly except the NT-05's which usually wear the center stripe too fast, even at lower pressure....

What size Rivals were you running and on how wide of a wheel?

[Cuda7050]

Originally Posted by Norm Peterson

Cuda - are you still on the OE SS wheels? 275/35-20's, I assume.

I'm with you on the relative effect of track session time vs autocross run times.

Thanks for the camber data points.


Norm

I have four stock 9" rear wheels with 275's on all four corners with 1LE sway bars.

[woodside783]

Originally Posted by Todd in Vancouver

Great idea for a thread.

With all the discussion on tires thought I'd throw another subject in here. AutoX really gets going next month locally so I'm off to Drivers Training in a week to brush up on my driving skills. Fact is my ZL is more capable then my driving skills are so all the horse power and tire in the world isn't going to make me any faster until I get better at driving. Just something to think about as we all head into racing season before everyone spends more cash on the cars it might be a better investment in yourselves.

Agreed

Cuda what size wheel are u running?

[crangie]

Hankook R-S3 in 285/35 20. This might be an interesting alternative.

http://grassrootsmotorsports.com/articles/top-tires/

[Bryan1LE]

There will be a 285/35/19 Rival, but it's not available yet. It's listed on BFG's website and I've heard that they will be starting production soon.

[Bryan1LE]

I was hoping for wider than 285 19" Rivals as well, but I was told that won't be happening this year.

[Rad_dsm]

Originally Posted by mp51998

Currently running BFG Rivals in a 285/35R20 on stock 9" wheels on all four corners. I have to run a spacer on the front to clear. Got them from ADM. I realize this is not optimal and will remedy before season ends. Ran this setup for the first time this last weekend. Huge improvement over the BFG Comp IIs that I was running in stock staggered size. Actually 3-4 seconds faster over the last time I ran this course setup on the old wheel/ tire combo. Very happy with them.

What kinda air pressure you running in the tires?

[mp51998]

Originally Posted by Rad_dsm

What kinda air pressure you running in the tires?

Last event I ran 34psi in the front and 37psi in the rear.

[So Cal Camaro]

Originally Posted by Norm Peterson

In Cuda's case, yes.

I don't know what cambers JDP or So Cal are running with, though, and there is still the possible influence of wheel width relative to tire width for Cuda.


Norm

I run 1.6 camber on the front and it is still an issue...need camber plates to get any more out of the front. The rear it is not as much of an issue for me, but the weight of the front does tend to wear the edge...I know running at Road America last summer, the carousel did a number on the drivers side front tire, followed by running a banked course in Nashville.