vms4evr

Hey guys,

Need a little help here with tire wear. I put on a set of Nitto R2. 275/40-17 front and 305/35-18 rear. Fronts come with 6/32 and rears come with 5/32.

Alignment: FR: -1.5 camber, 0 toe. RE: -1.0 camber, 1/8 total toe-in.

Experience: I have 9 events under my belt and 1 open wheel race school.

I now have 3 events on them all at VIR. 1st event on Grand East Course. 8x25min sessions for the 2 days. Tire wear looked fine. 2nd event on Full course. Got tons of track time, like 6hrs for the 2 days. Tire wear started to look more on the rear. 3rd event on North Course. 6x25min sessions for the 2 days. Rear tires are taking a beating.

Now I watched my tire pressures and set them to 34F/32R cold. Then checked after the sessions to make sure I didn't get over 40/hot. Had to drop about 2-4lbs after 1 session. Found I liked 38F/34R hot. Outdoor temps ranged from 80s in the morning to 90-95deg in the afternoon sessions.

Front tires look good and wear is even across both tires. And I still have half the tread left. Rear tires though different story. Drivers side the middle is almost slick but the outsides look ok. Passenger side there is still a tread pattern in the middle and outside edges look good. I've got half the tread on the outside edges but not in the middle. No chunking of the tires.

I ran with Comp Mode part of the day and no AH/TC the rest of the time. I did feel myself sliding the car more now I'm getting more comfortable pushing it.

I will get the tires flipped across the rims before I go back out.

So what are your thoughts on tire wear? (go ahead you can brutaly honest if it is mainly me driving poorly).

Graham

96LT1

That's about what I would expect from VIR.

**Mostly right-handers with the driver's side rear stepping out**

Worn centers say you are over inflated. Drop the pressure 1-2 psi on the left and .5-1 psi on the right and monitor. Get a pyrometer and take temps to tune in your pressures.

AU N EGL

40 HOT max. 32-34 cold before each run.

First time on flipped tires take it easy. Rubber has somewhat of a memery on which way it was going. Now with flipping the tires, there is a slight grip change for a session or two.

vms4evr

Thanks guys. I figured with road courses being more right hand turns than left hand that I should expect that. Thing is it doesn't seem to be bothering the fronts like that. I would have expected the left front to be worn hard on the outside.

I'll drop another pound or two next time out. I have to order a probe pyrometer or borrow one. I've never used one.

When I flip the tires they are going inside->outside across the car. So they will still be rolling in the same direction. But I'll make sure to go easy the first session out.

varkwso

I tend to be harder on the rears then I would expect. Guess hammering it out of the corners at the limits of traction is not the best for tire life . I have some worksheets/data sheets I picked up at a SVTOA event to help record your tire temps/pressures etc.... you really need someone to do it in the hot pits to get full advantage....

jeff

vms4evr

I'm also wondering how much the 1/8" toe-in in the rear is affecting it. Anything but zero toe I assume will drag the tires. Not that I want to remove it.

Next event my buddy will be with me running in a different run group. So hopefully we can work something out to monitor each others tires right in hot grid. How many minutes do I need to be out during a session before I should come back in and check temps?

Graham

wtknght1

That depends on how much you are sliding the car to be honest. You can get decent numbers though in 3-5 laps.