Looks like the transmission/shift point issue has been pretty well
covered, but here's one more account anyway. From the list response, I
think that we can say that any combination chosen will be more effective
if matched with a few important variables. A list might include such
things as horse power, car shape, track length, and composition, and
some others, I guess.
The 3 liter Buick is short on power, has a distinct taste for high
RPM's, and must push a car that is less than aerodynamically ideal. It
has a Muncie four speed, 26.3" tires, a 3.52:1 Dana #44 rear end, and
runs on the short course. That said, the following information may have
some meaning. With a cautious driver, the first run was conservative to
say the least. Nice easy launch, shift points in all four gears at about
6000 RPM. Results: 150 MPH first quarter average 159+MPH out the back
(tach indicated), average 155+MPH @ 7000RPM. The second run conditions
were slightly different (early morning, cooler temp), but we were much
more aggressive this time too. Hard launch, shifts at 8500 RPM through
all four gears. Results: 160+ first quarter average, 170 MPH out the
back (tach indicated about 8000 RPM), Average 164+ MPH.
Not really very scientific, but the speed differential is significant.
My guess is that if we keep our little RPM junkie happy, she will be a
good worker. And if we had more grunt, a slicker bullet, and a little
more room, the gear thing and shift points wouldn't be as critical. Then
again, if you're out of wind at the first mile marker, shift points and
gears are the least of your worries.
Don McMeekin, #1183
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