How to Find Torque From HP ?

Horsepower and torque are measures of an engine's output. In automotive engines, torque closely corresponds to how much force an engine generates when you first step on the gas, while horsepower gives an idea about how fast the car will go when you approach the rev limit, which occurs just before you must up-shift into the next gear. Automotive enthusiasts express this concept by saying that "torque gets you going and horsepower keeps you going".

* Get the horsepower for the engine and make sure it's expressed according to SAE standards, which stands for the Standard of American Engineers. If the horsepower is expressed in DIN units, which is more common on Europe, you'll need to convert by dividing the DIN horsepower by 1.0139.

* Multiply the horsepower by 5,252. When converting horsepower to torque, both figures depend on the speed at which the engine operates, which is expressed in revolutions per minute, or rpm. If you know the horsepower of an engine only at a particular rpm, you can calculate the torque figure for that specific engine speed only. If for instance, you are told that an engine makes 300 horsepower at 6,000 rpm and have no further information, you can use this data only to arrive at the engine's torque at 6,000 rpm.

* Divide the product from Step 2 by the rpm. The answer is your torque expressed in pound-feet. Returning to our original example, the torque figure would be 300 times 5,252 divided by 6,000, because the engine output was 300 horsepower at 6,000 rpm. The result will be 262.6 pound-feet. This is how much torque the engine generates at 6,000 rpm.