Torque vs. HP Revisted

[olddog]

Torque is the rotational equivalent to linear force.

Hp is a measure of the rotational equivalent to linear work.

You can put 400 lb-ft of torque on a stuck bolt, but until the bolt turns you have done no work on the bolt.


So yes, torque is the force that moves the car, but Hp is the measure of the work that is done on the car.

An engine turning 8000 rpm with 200 lb-ft of torque makes the same power as an engine turning 4000 rpm with 400 lb-ft of torque. If both engines are geared to go the same speed at their respective rpm, both engines will accelerate the car at the exact same rate, assuming the same drive train efficiency and car (weight).

If torque was the only thing that mattered, race cars would have diesels in them.