Gearhead Light app for iPhone and iPad

If you are a hobby gearhead, you’ll want Gearhead Light! Gearhead Light is the free calculator app that us gearheads use for performance automotive parameters. It calculates engine, gearing & tire parameters. Gearhead Light works in both standard and metric units so you can select the most compatible parts for your application.

Gearhead Light calculates or estimates:

Speed/Gearing
- Engine RPM from vehicle speed, gearing, tire size
- Vehicle Speed from engine RPM, gearing, tire size
- Tire Diameter and Cross section width from sidewall size
- Simple gear ratios based on drive and driven tooth count

Engine
- Displacement from cylinders, bore, and stroke
- Bore/Stroke ratio
- Static Compression Ratio
- Compression Height (piston wrist pin height)
- Head gasket volume (from bore and compressed thickness if round)

If you are looking for more please check out our paid “Gearhead" apps.
None of our apps have ads or use invasive phone permissions