Geekin' again

Jon Davis jfdavis@epix.net
Sat, 15 Dec 2001 12:18:54 -0500


George Roffe wrote:

> Jon Davis wrote:

> >and we know the hp at the crank so ....

> No we don't.

Did you read anything I wrote other than those 9 words? Here's the whole
relevant portion of what I wrote NOT taken out of context:

"Hp at the wheels is the same as hp at the crank (minus drivetrain losses).
We know the engine rpm and we know the hp at the crank"

A critical part of what I wrote is ***minus drivetrain losses***. We know
the hp at the crank minus the drivetrain losses. Where do you suppose they
get the torque numbers on the dyno chart?!? You don't see numbers on the
dyno chart in the many hundreds or thousands of ft-lbs... That is how much
torque is at the wheels. In 3rd gear a SR20 would be putting down more than
500 ft-lbs at the wheel. IIRC most people's chart comes back with around 125
ft-lbs for a stock engine, not 500+, so there must be some calculation
involved.

Jon Davis