Geekin' again

[Benjamin Moses]

OK, I want to throw a comment in here.  At the dyno, they put an
inductor thingy on your #1 plug wire.  Do all dynos do this?  I'm
assuming so.  Therefore, wouldn't a comparison between engine rpm and
dyno drum rpm reveal truer RPM and HP numbers??  I guess what I'm saying
is, isn't this method already employed??

<<Well, since hp=TxN/5252 (where N = rpm), we simply plug in the figures
for
T and N. T was calculated as above. RPM is the rpm of the drum (not the
engine of the car spinning the drum through the drivetrain). Therefore,
since we know N and T at the drum through data acquisition, we can
calculate the hp at the drum as well as the torque. Pretty clever, don't
you think?

So, now we know the torque (and thus hp) being applied to the drum. What
we
cannot do is relate the torque and hp at the drum (and thus the wheels)
to
the rpm of the engine. So, we need to also collect the engine rpm data
to
plot the torque and hp as a function of engine rpm rather than the drum
rpm.>>