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      03-24-2007, 09:57 PM   #34

Drives: MTA Monthly Pass
Join Date: May 2005
Location: NYC

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Originally Posted by T Bone View Post
What I am trying to say is RPMs are as important as Torque in rating the ability of an engine.

Horsepower is a measure of physics term called Work. The more work an engine can do, the faster it can accelerate the car. Work is Force multiplied by Distance. The Force for an engine is Torque. The Distance variable for an engine is RPM. I.e. the higher the RPM the more distance the engine exerting its torque.

As an example: An engine that generates 500 foot pounds of torque at 3000 RPM is less powerful than an engine that generates 300 foot pounds of torque at 8000 rpm.

HP (SAE) = torque X rpm / 5252
  • Torque Motor: 500 foot pounds X 3000 rpm = 285 HP
  • High Rever: 300 foot pounds X 8000 rpm = 456 HP
BMW's philiosophy is that it is more efficient to make power or work by creating motors that have moderate torque at high RPM rather than big torque at lower RPMs (Mercedes, Chrysler etc).

High RPMs over torque means that BMW can use lighter drivetrain components. This philosophy of design is also why F1 Cars turn 19,000 rpm, generate about 230-250 foot pounds of torque.

Peace out.
You see, your argument is torque at higher rpm is good (which I never questioned), my argument is the S65 has LESS torque at higher rpm, thus it does not a close ratio gearbox (which was our original topic).

Hopefully next time we get to discuss an interesting topic on the same page.