Tire size is an important factor in final drive ratio, is your speedo accurate? Tire size is the easiest and fastest item to change to adjust your final drive ratio up or down on tire size can effect your topend speed and bottom end launch,we use to carry three sets of rear Wheels 33", 34.5" and 36" depending on how we wanted to launch or mile an hour. 33" would get you mile an hour, 36" would get you Good 60' but your mile an hour would be less. This was one of the easy things you could adjust for track conditions, teamed up with trans gearsets and rear gearsets we could minutely adjust for each track. I think you would be happy with a 3.50 series gear, the 3.89 and 4.11 are great for street terror but you allready probably have a slight traction problem as it is, to really nail em' you need some cheater slicks,Drag radials. 3.50 gears are still great for the long hauls,3.89 and above are annoying for the long ones.The most practical solution is two carriers if its 9" they don't take long to change.Used 9" carriers are cheap on E-bay w/gears freshen up and go. Have Fun
Jim
