Force (lbs.) X Distance (ft.)
HP = ----------------------------------------
33,000 (ft.lbs./min.) X Time (min.)Torque = Lever Arm Length (in. or ft.) X Force (lbs.) Work: Work is done when force travels through a distance.
Force (lbs.) X Distance (ft.) = pounds foot of Work
Force X Length X RPM
HP = ----------------------------- or
5252
Torque X RPM
HP = -------------------
5252 Ok knowing these formulas what does it all mean? It doesn't answer your question does it? The real question is how much torque is necessary at the end of the RPM band? And why did that small light weight car that only produce 180ft/lbs goes so fast down the 1/4 mile. Would that car go faster if it had less horsepower and more torque. The answer is no. The short answer is because it already had more interia than it did opposing forces like drag, and rotational friction. Torque becomes a big factor in the lower RPM band where the body is in a static state and has zero inertia. Here is a very good example for you to think. Get a bike turn it upside down. When you first try to spin up the wheel you will notice that you will reach a point where no matter how much you try you can't seem to make it spin up any faster and that rotional speed of the wheel hits a limit. Lets say for just reference you were able to spin the wheel upto 10mph in 1 second. Now if you were to continue to swipe your hand against the out of the wheel you will find that you might be able spin it faster and faster and maybe reach a speed of upto say 25MPH yet at no point in time did you actually increase your own horsepower. Now here is the important factor. Say you are riding that 10 speed of a hill of say a 30 degree incline and you want to make it up fast as you can. Do you think from a dead stop start at a high gear or a slow gear? You would start usually in a low gear and work your way up thru the gears and until you hit your maxinum load rate that was no longer caused acceleration. So the answer to your question how important is torque on the top end? Not as it on the bottom end because you can make use of gear multiplication. And the true secret of how to make a car fast is not just horse power and torque but effective use of gear ratios. And if you really thinking about it you will realize that force being constant you can increase and reduce torque by adjusting the leve arm. IE adjust the gearing. BTW did you post this once before.
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00:44:21 01/20/04
