Engine Horsepower Calculator
The following calculators estimate a vehicle's engine horsepower based on its weight and its performance over a quarter-mile run. The vehicle's weight should include the driver and any cargo.
The Elapsed Time (ET) Method
This method uses the vehicle's weight and the time it takes to complete a quarter-mile (402.3 meters).
The Trap-Speed Method
This method uses the vehicle's weight and its speed at the end of a quarter-mile run (trap speed).
Horsepower vs. Torque
While often discussed together, horsepower and torque measure different things. Torque is a rotational force—the "pulling power" that gets a vehicle moving from a standstill. Horsepower is the rate at which that work is done, determining how fast a vehicle can go. A tractor has high torque for pulling heavy loads but low horsepower, while a race car has high horsepower for high speeds but may have less torque.