Racing Gear Ratio Calculator

If you are customizing, building, tuning your performance race car and you are looking for accurate and easy gear ratio calculations this is the app you need. Designed by Fortin Racing, a industry leading gearbox and transaxle manufacturer, the app is user friendly and provides all the needed information for track side gear ratio adjustments.

You can quickly check your intended ratios and calculate final drive, mph and rpm drop per gear. Instantly see what a huge difference an adjustment to your ratio, rpm or tire size can make to give you the competitive edge. This also includes an underdrive (Drop Gear) option.

Stop messing with pen and paper or trying to remember which math equation to use when you can rely on this app to be consistent every time.

Enter in 2 separate configurations for comparison. Send the comparison to the printer to get a hard copy of your calculations to have on hand.

Save and Load feature allows you to store your settings to load them later. Save your gearbox ratios for each track or different transmissions for future reference.

Crew chiefs and gearbox builders must have this app!