Do I need 1 or 2 New tires?
 

Unfortunitly I blew out my left rear tire running over some wood that was dumped in the middle of the road and I was unable to avoid it. The damage to the tire is not reparable. The question is: I have about 8,000 miles on the current set of Donlup SP Sport 8090 tires. Shold I replace both rear tires or can I get away with only replacing one? Also, I have not done many burnouts or drifting with the current set of tires. Thanks for you help and advise!!!

I would do both.

I would do both, if you figure the tires are good for lets say 30,000 miles then you have used them for just 1/4 of thier life span. If you put a new tire on they will be slightly different in size. If it were my car I would buy 2 new tires.

You should always replace tires as a pair to keep the handling characteristics the same.

The other tire can be a spare. Find another wheel to mount it on and throw it in your garage/basement for emergency use.

Chris...

If it's regarding the rear tires, ALWAYS replace both.
Because if the two rear tires are of different tread, the left and right axle will spin at different speeds during highway cruising and heat up your differential until it blows.

This is also the same for 4WD, because they have three differentials, they need to replace all four if one blows... sucks huh? ^^

I have had this happen to an old car that I had. It heated the rear pumpkin up so hot it turned white and smoked off all the differential fluid. No damage was incured but it still sucked to have it happen.

I doubt the tires on an AWD car will wear equally front and back anyway, so I don't see why you'd have to replace all 4 at once. Even if they're using 50/50 front/rear drive they will wear differently because the fronts turn left to right :p