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Old 12-31-2012, 10:44 PM   #744
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Quote:
Originally Posted by zooki View Post
You guys have to remember that the only thing a dyno measures is torque. Horsepower is mathematically derived from the torque measurement. That's why the horsepower & torque will always be the same at 5252 RPM. Horsepower is just torque over a certain period of time.
Not all dynos measure torque. Also, application of torque over time doesn't necessarily equate to hp. But I know what you are saying, just hear me out.

Torque is a potential energy. A force. Once that force becomes kinetic, it can be measured in HP. Applying 100lbs to a crankshaft creates 0hp until that crankshaft starts to move. Until movement occurs, its just potential energy.

Some inertial dynos read whp, then use inductive pickup clamps as a means to get wtq number from an RPM signal. They measure the acceleration of a fixed ballast weight to determine HP. This is the most accurate way to measure HP by its very definition. Of course, there are deviations from those numbers with competing dyno manufacturers who seem to think its ok to treat HP as an arbitrary number. That is another topic altogether.
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