NewFoundPower

They are Falken RT-615s, 315/30 and 255/40 on stock C5 Z06 wheels. I'm concerned I'm getting into the carcass rubber on them, they seem darker on the outside corners, and I'm at the wear bars on the insides. Am I ok as far as how far they're wearing over the outside corners? How do I know if I'm getting too close to the side wall? I've heard to keep an eye on the ring and triangle cast into the rubber at the corner but wasn't sure how far is safe.

I'm planning to go with a set of Kumho XS next in 315/30 and 275/40. I'd obviously like to get those soon but if I don't need to spend an extra $1000+ for the next event (NASA TT at TWS) then I'll put it off one more. I'd rather be safe than sorry though so if it would be a better idea to replace them I will. Let me know what you think. Thanks!

Aardwolf

They look fine. I've got some that went to metal showing, then they are done!

fhturner

Holy schnikes! That is a huge difference in width front to rear! ...I would think that thing pushes like a pig. You're still fine to use for another weekend, tho...just keep an eye on them after each session.

Garick

agreed

gkmccready

Screw the wear bars for your "track" tires. That's when they start to get good. When they're bald, call them done. Shortly after that it's cords, and then steel belts. I nearly cried when I pulled my tires off the car this past weekend before at least one of them was showing cord...

NewFoundPower

Yeah I was wondering whether to go with the 255 or 275 when I bought them and got worried about the 275/40/17 being almost as tall as the 315/30/18 and making the front end raise up too much. I did another search and the 275/40s seem to be much more common so I'm going to try those with the next set.

I spend most of my track time at TWS, which is fast and has mostly long turns, so it hasn't been too bad - but is definitely noticeable in some areas. However, I have a tendency to be pretty heavy on the brakes in tighter turns and my tires are definitely the limiting factor on entry (ABS every time). I am probably over-compensating with the brakes which keeps it in check a bit, so when I get some 275s that are a little stickier I think that will help me speed up once I get used to them.

I just watched the video from my last time out again and recognized a few areas where it does push pretty bad, I hadn't thought about how much the tire width difference will affect that. I just thought I wasn't getting on the brakes soon enough!

http://www.youtube.com/watch?v=0I-aYHf8oUI



Would it be worth considering buying new fronts only for the next event? Or is mixing tire brands a bad idea?

Also - what do I need to keep an eye on between sessions? Just look for cords or am I really seeing carcass rubber there that needs to be monitored?

NewFoundPower

Lol!! Good point, hahaha. I don't want to get rid of them before I have to but I am ready to go faster!

WBHighwind

I consider the amount of cords showing to be the wear indicators for track tires.

Last C5

That's what the cords are for, right?

AU N EGL

tread depth has nothing to do with grips. For street tires when the wear bars show, the grip is right.

Jason

How many weekends have you used them so far?
HPDE or autox?

NewFoundPower

I have 5 two-day HPDE/TT events on these tires and they are about 9 months old.

I was less concerned about the wear bars than I am the change in color of the rubber around the edges and the amount of wear at the tread/sidewall corner (mostly at the front - shows up best in the 4th pic). Last time I asked people mentioned that "carcass" rubber would be darker and more slippery, so I was wondering if I am getting there on these.

I recently bought a Longacre durometer guage - if I check at different locations on the tire should they all be relatively the same? I haven't used one before so I'm not sure what to expect, I mostly wanted to see the difference between before and after a session.

VetteDrmr

One other thing you can do is to have your tires flipped on the wheels, so the meatier inside edges move to the outside (based on you comment that the outer edges were showing measurably more wear).

Also, don't worry about running the tires in the "reverse" direction, unless you're running in the rain. That will allow you to switch the right tires to the left side to balance wear out that way.

HTH, and have a good one,
Mike

CHJ In Virginia

Those tires are just getting good now. Drive them till they cord !!