SharkMan wrote:
> Hello,
>
> I have a Mustang with a 347 putting out 475hp. I plan on road racing
> this car, no drag racing ever. I am a driver, not a mechanic, so I
> looking for a second opinion. The shop doing the work on the car wants
> to put in a 3.73 gearing. I was thinking 3.27 would be better for
> economy and top end performance. I was hoping someone out there could
> help me with this.
>
> Thanks!
>
> David
>
There is no one perfect gear for all road courses.
That's why professional race teams carry multiple
gear sets to the track.
If you're only racing at one track, it's a lot
easier. What is the top speed you'll expect to attain?
Try and select the gear that places you just past the
peak of the torque curve at that speed in 4th (1:1) gear.
That will be a good place to start. But expect to
make a change or two as the season progresses.
Optimally, you'd want a 8 inch rear, with multiple
center sections. The center section can be swapped out
in less than an hour the first time. All it takes is a
couple of hand tools. Even a non-mechanic can do it.
The 8.8 is plenty strong enough, but since it has
an integral carrier changing gears is time consuming
and requires special skills and tools. A 9" rear is
stronger, but also requires more power to run it. A
well built 8" will last forever on a road course, will
be lighter, and will deliver a little more HP to the
ground.

--
..boB
1997 HD FXDWG - Turbocharged!
2001 Dodge Dakota QC 5.9/4x4/3.92
1966 Mustang Coupe - Daily Driver
1966 FFR Cobra - Ongoing project