At some point you may be curious as to your top speed in a certain gear, or how changing your tire height will effect your mph at the end of track. There are endless variables with the different transmission gearing, ring and pinion ratios, and assorted tires. The following calculations will give you the information you need to make an educated guess as to how your car may perform.
Engine RPM: RPM = MPH x Transmission Ratio x Gear Ratio x 336 Tire Diameter
Miles Per Hour: MPH = RPM x Tire Diameter Gear Ratio x 336
Gear Ratio: Gear Ratio = RPM x Tire Diameter MPH x 336