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saw a vw passat commercial.. appeared as if a lady was test driving the passat with the salesman in passager side.. he instructs her to pass a car.. she was then impressed with how it passed.. here's what gets me.. he then says something about "...at lower rpm's, but then hp kicks in to do the rest of the work".. something sound fishy about that to ya'll?
 

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I think he said "at lower RPM the troque does the work and then at high RPM the HP takes over". So really what he is saying is true but it means the motor has a poor power band ie large gap between the peak foot pounds and peak horse power.
 

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Originally posted by Optra bob@Feb 29 2004, 11:07 AM
I think he said "at lower RPM the troque does the work and then at high RPM the HP takes over". So really what he is saying is true but it means the motor has a poor power band ie large gap between the peak foot pounds and peak horse power.
Don't you mean a broad power band? The rpm range between peak torque and peak horsepower is generally known as the 'power band.' Since horsepower is a derivative of torque, the range between peak torque and horsepower generally represents a relatively flat torque value, providing optimal acceleration.

Engines with broad torque curves tend to feel powerful right across the range. Engines with narrower power bands (closer torque and horsepower peaks) tend to require more gears to keep the engine in this responsive range.

This, or course, is a generalization. The Corvette V8 has a torque peak of 400 at 4400 rpm and a horsepower peak of 400 at 6000 rpm, giving a powerband of 1600 rpm. However, that engine still makes a substantial amount of torque below 4400 rpm - in a car as light as the Corvette, it will accelerate very hard at much lower rpm values.
 
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