Dave_D

Hi all,

I need some input from the pros -- don't know if what I'm feeling from my car is right or not:

Yesterday, I received four shiny new Michelin Pilot Sport PS2s on my '99 996 and, given the odd treadwear on my outgoing tires, an alignment. When I mentioned autocrossing and aggressive driving habits, the shop recommended an increased camber (but would not provide hard data for the settings applied, so I can't report them here).

No doubt, the car is gripping better, even in the 200-mile burn-in phase. In straights and modest turns, all is normal -- perhaps a bit squishier than the previous Pirelli PZeros.

What's new is a noticeable "gripping threshold" -- the tires seem to "grab" or "kick in" at a noticeable point in harder turns. The initial sensation is one of rolling onto your sidewalls -- a bit scary -- but turns immediately to, for lack of a better word, "ultra-grip." The car feels great, as if feel for the road and slipping are momentarily enhanced. Granted, not being used to it, it makes for hesitation at turn-in, but extreme comfort through the rest of the turn. In fact, the sensation is so inviting, I'm finding myself blipping the wheel or turning in late in order to engage the ultra-grip where it might otherwise not happen. I know this is wrong -- all input should be smooth -- but lesser turns just feel mushy by comparisson. The grip is good.

What am I feeling? Is this normal and desireable or a sign of something not-quite-right? I have checked my sidewalls for wear and there is none.

Any advice is appreciated.

Dave

adsc4s

With additional camber, your tires will wear on the inside quicker than the outside if you do mostly straightline driving. If you are driving in the twisties, as you approach an apex, hit the brakes hard and then accelerate hard out of the corner. The "squatting" of your car along with the camber will insure that a majority of the rear tires are planted on the surface.

BHMSC

If you went from extremely worn tires to new tires with full tread depth, you may be feeling the squirming of the taller tread blocks. When I raced showroom stock cars, I noticed the same effect when switching back and forth from full tread street/rain tires to "race" tires with the tread cut down to 4/32" depth.

Dave_D

Aha!!! I bet that is exactly what it is! The other symptoms I mentioned would appear to corroborate this: squishier, smoother ride, etc. Last weekend, my wife & I autocrossed the car in the new tires. Perhaps we wore a sufficient amount of tread off or I'm otherwise just not noticing the odd sensation anymore.

On a side note, the tires performed amazingly at autoX. Now, I just need to improve my technique a little; reduce the pushing and save a little tread for next time.

Thanks a million!

Dave