How to Calculate & Find Engine Torque
- 1). Torque is force multiplied by a distance. In British units, torque is measured in pound-feet, or lb-ft, and is usually denoted by the Greek letter tau.
- 2). Power is equal to a force multiplied by the speed. In British units, horsepower is 550 ft-lb / s, or foot-lb per second or 33,000 ft* lb / min. RPM tells the time for an object such as the shaft of an engine to rotate when there is no load.
- 3). Torque is equal to 5252 x horsepower / RPM. The constant 5252 is found by using hp and radians, so it is 33,000 / 2 x Pi, where Pi = 3.14.
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