vette ruminator

At the beginning of last summer I bought a set of MPSCs to use for HPDEs. I drive to the track and back, then take them off. They have a total of 6 track days on them, with roughly 36 track sessions, 15 min each. I had been running them at 28 psi cold front, 30 rear, and (as I recall from last summer) they were about 36 psi all around when they were hot.

My fronts have worn as in the pictures you see, with the band just inside the outer tread pattern tapering down towards the wear bars. Once I saw this pattern, I backed off on the pressure to the pressure recommended on the michelin product info: 25 cold/32 hot front, 28 cold/36 hot rear (the cold temps are where I start, the hot temps are the ideal temps from Michelin; I was in that neighborhood). I think it has stabilized, but I did not do tread depth measuring along the way.

Is this pattern normal wear for these tires? Is it not normal and it happened because I was running too hot? Is it an alignment issue (I am running stock alignment as the car is a daily driver except the 6 track days).

I'm trying to get the maximum use out of these expensive tires; how do I know when they are spent (besides the wear bars alone?) I have alternated right front to left front, right rear to left rear between events.

Thanks for your input!

Front tire wear pattern with tapered band inside outer tread pattern:



Rear tire wear pattern more even:

0Luke@tirerack

That is not an uncommon wear pattern at all and it seems you have the pressures pretty figured out pretty well.

what is happening is that under high cornering loads the tread elements are flex to the side (similar to how a winter tire makes 'biting edges') and have accelerated wear on the leading edge of the circumferential tread elements.

here's a visual I used to explain winter tires in my BLOG



now if you wore off the leading edge of each block when the tire returned to a static state you have the exact wear pattern of your tire

vette ruminator

Thanks Luke. Anything I can do to make the tires last longer (besides driving slower)? If I am at the lower pressure, will alignment make a difference in this wear pattern?

How do I know when these tires are spent? Seems like I can't rely on wear bars alone for these track tires...

vette ruminator

0Luke@tirerack

more negative camber (within reason of course) is never a bad idea.

when you see metal they are officially worn out

'Merica

I didn't want to make a new thread and this shows almost what I'm seeing so I'll post here. I work with commercial tires all day, every day, so this is pretty "normal wear" for those tires, but with so much less tread, I'm thinking I may can salvage what's left on these tires.

On nearly all 4 corners, I am seeing almost 1/32 difference from inside groove compared to the outer most groove. 1/32 more on the outside than the inside of the tire. I am running 29psi on all 4, should I adjust my psi to a lower amount- maybe the 25/28 like noted by the OP? Or possibly an alignment issue? I'm not seeing any other irregular wear on the tires, but outside I'm seeing 5.2/32 and inside of tires 4.2/32.