Wear on Cups

[kbird]

Can anyone help? I have Intrax/Cups and am suffering from massive wear on the inner edges of the fronts. I have the adjustable top mounts that allow the camber to be adjusted to -2.5 degrees for the track but yesterday a Lydden Hill I had to leave early as the more loaded nsr front tyre had delaminated due to wear on the inner edge and had the second layer of canvas showing over the first 30mm of the tyre. The tyres have done four track days, Rockingham, Combe X2 and Lydden yesterday. Is this level of wear what is expected? I would have thought the most wear would be on the loaded outer edge? The tyres are run at Michelins recommended hot pressures and -2.5 degrees is also in line with their recommendations, what do you think?

Edited by kbird on Sunday 24th May 12:45

[Steven_RW]

I ran my intrax with 2 degrees camber and ran it this way on the road, I WASTED the inside edge of my tyres in no time. I believe it would seem that you have too an aggressive front end Geo. If I was to run an e46 m3 on the road again, I would set it at a MAX of 1 degree camber and nothing like 2 degrees toe out. It just kills the tyres in no time.

COnclusion from me: Ur geo is either not set where you asked it to be (toe and camber and castor) or your settings are too aggressive, or you let your tyres get too hot.

Cheers

Steven_RW

[RatBoy M3CS]

Have you lowered the car on the front, and pushed the turret tops over to -2.5 at the same time....?

Have you checked the toeing ..?

Too much toe out will produce exactly this wear pattern.. mine kills the inner edges just as much as the outer shoulders.., but get it geo'd to make sure what you have to start with..

At -2.5 frt neg, 32psi hot works OK for wear / grip, but not ideal, they need a bit more to keep the wear off the sidewall...( -3.0 neg...)

But TBH 4 full days on a pair of fronts with track geo is pretty much what i would expect..

If your doing much road work on these settings, expect to be buying plenty of tyres.. they wont last for sure.. you will need to stand the fronts up to -1.0 for that..

I run -3.0 neg with 2mm total toe out front for the track.. but when you stand the front end up to -1.0 neg the effect on the toeing reverts back to a toe in.. which is what you need for road work.. you could consider this route..

Toe-out adds to the wear rate, but does help a little with the understeer.., it does need a it more holding onto tho'... as the steering is very direct..

Edited by RatBoy M3CS on Monday 25th May 17:53

[kbird]

Geo check being done Thursday, then new Cups but filled with Nitrogen........

[RatBoy M3CS]

Let me know how much more temperature stable they are...

I think you will find they will still go up 2-3psi, due to the moisture, as they dont get purged completely on a nitrogen fill..

Usually I start out on 30psi for 5 laps, come in, reset to 32 from 38ish, go out for another 5 laps.. then reset again to 32 from 34-35.. then good to go, but pretty much the first session is just to warm the tyres up, and then work on the car balance when its all up to temp.. by tuning the dampers.. final balance adjustment I do on the rear pressures, if it needs it on the day..