Took my car to the track for the first time and made a half-dozen passes. Through the last part of the track I hear what sounds like bad detonation from about 5000rpm and up. It doesn't happen in first and second gear and only at the top end of the track. It doesn't happen when I rev it in neutral (while stopped) or lug it from low revs in too high a gear on the street. In fact, I never hear this sound on the street, only at the track.
My car is an 04GT five speed, 14000k, full weight (plus 300lb. driver), stock motor, stock Goodyears at 35psi, running on Chevron 87 octane fuel. I started at 15.5 at 80 (let off way before the stripe) and got it down to a 14.8 @ 94. The last three runs were all at about 93-94mph.
Any ideas? Things to check? Does the mph seem par for a stock GT?
I'm thinking its some type of detonation but can't say for certain. I don't want to wreck the motor but I'm hooked on running at the track. It takes a lot more skill than I thought (and got) to make a decent run.
Thanks
My car is an 04GT five speed, 14000k, full weight (plus 300lb. driver), stock motor, stock Goodyears at 35psi, running on Chevron 87 octane fuel. I started at 15.5 at 80 (let off way before the stripe) and got it down to a 14.8 @ 94. The last three runs were all at about 93-94mph.
Any ideas? Things to check? Does the mph seem par for a stock GT?
I'm thinking its some type of detonation but can't say for certain. I don't want to wreck the motor but I'm hooked on running at the track. It takes a lot more skill than I thought (and got) to make a decent run.
Thanks