On the topic of the 15 vs the 17 wheel and tire. Having run both.... the size and construction of that Radial Pro acts like a big shock absorber. It noticeably softens the initial hit on the drivetrain. Anybody else experience where the initial hit moves the car and picks the front end up (mini freeze frame wheelie) and then the front comes down and the tires break loose? One of the contributors to that is the shock that ET-R at 20 lbs throws at the track on the initial hit. It requires more of a soft peddle driving technique to address that. The big Radial Pro absorbs that initial shock, and at 15 lbs.... squats and puts down a long footprint that keeps the tire glued to the track. While this might not produce a better 60’ than the 17 when under perfect conditions, it will do it more consistently. You’ll forget about that wondering what’s it going to do this time thing.