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xxChrisxx
xxChrisxx is offline
#46
Mar27-09, 12:54 AM
P: 2,032
Its the force (engine) that creates the power (engine) :P hehe.

Torque - Ability of engine to do work
Power - Rate at which said work can be done.

Well the horsepower curve is a function of the torque. I believe the angle you are coming from is that: two cars travelling a constant speed along the road (the one with less torque requires it to be in a higher rpm band) both floor it. The answer would very corrctly be that they would both probably accelerate at the same rate.

However, the other car would require different gearing to do this. This was why I was harping on about it earlier.

This didnt come across in your original question. As two identical engines but one with more torque to me means identical gearing and ataring form the same rpm. In which case the engine with the larger torque would win out. (This was why your arguements were quite confusing)

The practical upshot is that, high torque engines accelerate very well in the bottom end of the rev range. but higher revvers accelarate better in the upper rev range. In very slow corners (such as a hairpin) it's quite likely that a car with a narrow power band is likely to fall out of the optimal range. This is very true with sometihng like a formula 1 car where the power band is about 1500RPM.

This led me to my point about the slow corners thing. A huge V8 would out accelerate a smaller high revving engine initally, but then the high revver would have a relative increase in acceleration as it gets down the straight.

This then leads into useful power band and that Jeff said about lots of narrow gears are needed for the high revver as its peaky but a big lazy V8 would need less to get the same job done.

EDIT: I think we've just argued ourselves to a similar conclusion! Damn! You thinking was pretty much ok, but like you suspected its your terminoligy that was incorrect (and what got me all :S). I'd like to say im sorry for being a bit curt with you earlier.

One thing you always have to keep in mind though and this is the most important thing. Its NOT the power thats accelerating you, its still the torque produced at the engine that is determining the rear wheel force and therefore acceleration. So dont think of it as 'RWHP determinign torque, its torque determining RWHP!!