Automotive & Engines

Basic

Horsepower from Torque (Imperial)

Horsepower from torque (lb-ft) and engine rpm.

Formula

HP = \frac{\tau \times N}{5252}

Variables

HPHorsepower

τTorque (lb-ft)

NSpeed (rpm)

Example

250 lb-ft at 5252 rpm: HP = 250

Did You Know?

Torque and horsepower curves always cross at exactly 5252 rpm — a quirk of the constant in this formula.

automotive horsepower torque

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