Dean;
To respond to your response, and clarify what I said....
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Torque = the force that an engine can apply at a certain speed. This would be important if there were no transmissions. But there are...
HP = The amount of work that will be done after everything is passed through the transmission, wheels, etc.
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Engine HP (measured at the crank or the wheels) determines how much work can done at the rear wheels.
Two engines, both put out 100 lb/feet of Torque. Once does it at 1000 RPM and the other does it at 2000 RPM. Which would you rather have (assuming that you have a transmission)? I would rather have the 2000 RPM engine because I could gear it down and do twice as much work at 1000 RPM as the 1000 RPM motor could. This is a simple analogy and it gets more complex once you throw in other factors such as noise, width of the torque curve etc.
Here is an interesting comparison: a NASCAR engine versus a 3 liter F1 engine. From an academic perspective, I might argue they have similar ultimate performance. Essentially (On the back of an envelope calculations) they both get about the same amount of work (HP) out of a given unit of air.
NASCAR Engine: 6 liter, 8 thousand RPM. 800 +/- HP
F1 Engine: 3 Liter, 16 thousand RPM. 800+/- HP
Having been to close to both at full song, they both put out about the same number of decibels -- REALLY LOUD
. But then they are both pumping about the same amount of air. But I believe that this goes back to the engineers measure of engine performance: Brake Mean Effictive Pressure which is the force exherted on the piston if my memory is correct. If you can get that number to move off of the curve, then you really have something!