Well... I may have just ended my autocross season early. My back right tire sideswiped a curb pretty harshly, which wouldn't concern me really if there was no abnormal noises or bent looking rims, but this time I put a small (about 1-inch long or a little under) cut in my sidewall, in which rock chips from the yellow curb were embedded.

Now I won't be autocrossing until I can get new tires (or a set of really reasonably priced rear Michelin Pilot A/S plus's), but the question is it ok to drive on? I didn't look too deep, maybe a quarter of an inch at most in a downward angle, only slightly toward the inside of the tire. I'm just getting ready to leave tomorrow to make a 170 mile trip, and I'm concerned that it might exploded on the highway. Does anyone think it's still safe?