# RPM Range Computator By Bowling

The following simple computation determines engine RPMs at interval MPH,
Tire diameter, final (differential) gear ratio,
and transmission ratio (usually 1.0 for high gear, or something like 0.7
for overdrive). Additionally, a tire growth factor is included, which
alters the tire diameter by factor times MPH squared, useful for racing
slicks. A growth factor of zero removes the "growth" influence.
Also, for automatic transmissions, there are torque converter "slippage"
factors which help account for RPM "loss" through the transmission.
These are entered as two sets of transmission efficiency values (percent)
at given RPMs, which are linearly interpolated. Remember, this effect
RAISES the RPM, because the engine must turn faster to compensate for the
losses.

Bruce Bowling

bbowling@earthlink.net

Bowling Superior