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      05-08-2012, 09:20 PM   #77
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Originally Posted by swamp2 View Post
Not quite. It is also incorrect to think of one quantity as physical and the other derived. Neither is less mathematical nor more physical. It is just that given one (and engine speed) you know the other precisely. You should read some of the length debates and discussions here in old topics on the forum to better understand these fundamental concepts. There are other much simpler ways of describing the differences. E.g.:

-Peak in gear acceleration will occur at the rpm where peak torque occurs (not counting minor corrections from parasitic losses)..
-Peak acceleration at any given speed occurs by making peak hp (mostly equivalent to saying lowest gear = most acceleration).
-Engine torque is meaningless without speaking of gearing to describe any aspect of vehicle performance
-Overall vehicle performance is much more dependent on peak hp than peak torque (again refer to point above)
Again, we are saying the same thing. It is what I am implying all along: horsepower is what counts for performance.

Power on the input and output sides of a gearbox will remain the same (disregarding losses), however torque will not (unless it is a 1:1 ratio gearbox).

I do not need to read forums to get educated in my field of work. I am an aerospace engineer specialized in engines. I have worked a big chunk of my career in the test department around dynos doing power calculations all day long. I can assure you, power is a mathematical concept. You cannot measure power by itself (same as energy for instance). Power is the rate at which energy is used. You need to combine more than one measurable element to derive power. Force x distance / time, electrical tension x current, etc... There is no such device as a pure "powermeter" .

Last edited by CanAutM3; 05-09-2012 at 05:08 PM.