I would say that you would want to do what DV8 said...I was not fortunate to get more than ONE run at the track on Test n Tune day...my track conditions were horrible, and I ran on my 18's, full interior, spare tire, stools, etc in the trunk, and had to piss like a **** racehorse after sitting in the car for about 3 hours waiting to get my FIRST run. I think I ran a 15.9....my 60' was too high, and the Prelude stripped of interior ran a 15.56...and he was spraying. I know my bad time was also due to my loss of traction going into 2nd gear...I span my tires from 0-40, which sllowed me down, big time. I didnt care at the time, I was hot, had to go to the restroom and the track was a mess..a Supra ran into the wall on my side 45 minutes earlier, so grease and oil and coolant still on the track made for bad conditions. My advice is to try again, with your 17's, and try to stage as far back as possible so you will have more room to take off. Holla back.