Overinflation and excessive treadwear in center of tire.
 

When I pulled off my stock Bridgestones last fall, I noticed that the tread in the center of the tires was completely gone, even though along the inside and outside edges there was some tread remaining. This surprised me, because I only significantly overinflated the tires one time for an autocross event during which I had maybe 5 minutes of total track time. Granted, I did beat the hell out of the car and it was extremely hot outside for the event. Still, during normal driving I had the tires inflated to spec or maybe 2 or 3 psi higher. Can slight overinflation result in this type of uneven treadwear? Did anyone else experience something like this?

Looks like I need new summer tires after only ~20k miles on the Bridgestones. The wife is not happy at all about this. For this reason, I'm going with the cheap Kumho Ecsta SPT tires, which hopefully will last MUCH longer than the Bridgestones.

No - I routinely inflate my tires like that and the wear is even.

Hmmmm, maybe it was the autocross event then? I inflated the tires to around 40 psi for the event, but like I said I only had 5 runs at around 60 seconds a pop.

Did you inflate your tires to 40 psi when cold? That's really near the maximum pressure for any tire... and then you went burning the rubber which should really increase the psi even further.

I know nothing about autocross, but that seems really high for racing tire pressure. Did you have any grip? Were you sliding all over the place? When racing superbikes, I inflate the rear tire to 29psi cold. After 1-2 laps the psi in that same tire becomes 35pse just due to the heat generated. Thats a significant increase in heat (and psi) which road riding can never accomplish. That same tire when being used for road use is recommended by the factory for 42psi for usual use.

I been running 36-40psi (cold) for street cars and have never worn the middle of a tire.

My guess is that you will find more grip if you reduce the tire pressure. Frankly I'd like to know more about what pressures most guys use at the track for car racin'.