REVHARD

Having issues making the car turn all of a sudden and need help from you guys. The car is a c5 Z06 with DRM Bilsteins, GM T1 sways and Nitto Nt01 275/40/17 up front and 315/30/18 out back.

I've noticed the outside half of my front tires to be extremely worn out. The inner part of the tire still has the grooves for the tread. The tires have 7 track days on them and have been fantastic until recently. Heat cycled out just in the front? Since the front tires are much smaller than the rears?

The car has -1.7 camber up front and -1.0 out back. Should I dial in more camber or is something wierd going on during hard turn in causing the front to create positive camber. I had the alignment on the car checked and everything is perfect...I'm stumped!

brkntrxn

NT01s don't normally heat cycle out that quickly, but it is definitely possible and sounds like the plausible cause.

Last C5

You have half worn out 275s up front and good 315s in back and you're getting push. Under those conditions that is what's expected.
Square set ups, 2.5 camber up front, and lighter sways up front can cure almost all of it, but it will still understeer on some corners. C5, C6, and C7 all have some understeer built into them.

REVHARD

Yes I think it's possible that the fronts are heat cycled out but I wouldn't say they are worn out. Just the outer half or 3/4 of the tire is wearing to an extreme. I thought I read somewhere the T1 bars help cure the outer tire wear because it drastically decreases the roll center.

I started thinking that the rake on the car might be to aggressive for some reason, causing the front to get to low under hard cornering causing the strange camber affects?

I've been really thinking about running a square setup as so many people talk about it and I've seen quite a few guys at the track running it. I guess I'll give it a shot.

Painrace

Try more front tire pressure and less rear tire pressure. Go 2 psi at a time.

Jim

hungryhippo

Nt01's get stickier as they wear down and they shouldn't be wearing like that. I would double check your alignment and your upper control arm bushings. Sounds like you need more neg camber or your bushings are shot so it adds +camber during cornering.

REVHARD

pulled the front wheels off...the upper control arms are beginning to wiggle their way out from the bushing and going towards the front of the car....damn! That's probably it.

JeremyGSU

I used to run 275/40/17 & 305/35/18 Nitto NT555 RII's. Stock it understeered pretty bad going into corners. I then got a track alignment and the JOC stage 1 suspension. This helped.

However, the biggest change I have made was going to 285/35/18's and 305/35/18's. I couldn't believe how much of a difference changing that tire diameter did. It turns it SO much faster. I still drive my car on the street with 275/40/17 and 295/35/18 and every time I put my track set on at the track I have to re-learn the steering as it turns in completely differently.

If you're still unhappy with your setup down the road try that and I think you would be pleased.

As for the wear, you're probably just not getting enough negative camber.

REVHARD

The plan next year was to up to a wider tire up front and an 18" wheel. I was thinking of making the move to Toyo R888's in 295/30/18 up front and keeping the 315/30/18 out back. I wish Nitto would make sizes compared to the R888's as I'm familiar with that tire...some guys swear the Toyo's are better while other's say the Nitto's are better to people saying they're the same.

JRL

Something else to check, ride height, I ran revalved bilsteins and if the front end was too low, I was riding on the bump stop which caused push.

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John

skxf430

I would stick with the NT01's over the 888's. They are stickier and last longer.

theseal

A c5 z06 needs only alignment. - 2.7 front camber. The t1 stuff is ok for big tracks especially with some aero but will generate a little more push.