DragStuff

My co-woker is tubbing out his Stang.

His old setup was 434sbf, C-4, approx- 1000hp w/ 300 shot, 5000 stall, 28" tires, 3:73 gears shifting at 7200rpm.

His times were 8.94 @ 154mph.

His new tires are going to be 32" x 14" x 15" Hossiers.

He was told 4.56 gears. The program I use said 4.63's but then I thought, does this program take in consideration
for NOS?

Any thoughts on what the new gearing would be using the same drivetrain components?

Thanks

Bruce

If it can handle the high rpm at the end of the track, I think more gear is better. Although I have 3.70's in my car it also has 28" tall tires.

I ran 4:30's with my 32's in the 1/4 on NOS, shift point was about the same...

The formula I used was: tire dia x RPM/ (336 x MPH)

Is this a good formula to use?

After I changed some numbers I came up with 4.49, which is close to the 4.30's.

Bruce

His old setup was 434sbf, C-4, approx- 1000hp w/ 300 shot, 5000 stall, 28" tires, 3:73 gears shifting at 7200rpm.

His times were 8.94 @ 154mph.

His new tires are going to be 32" x 14" x 15" Hossiers.

******

I used the above numbers and hit the Mark Williams (http://www.markwilliams.com/calculators.aspx) website - it's what I use for my gear / topend calcs, and came up with the following.

Using 154 mph as the target, here's what the calc came up with, for both the old and the new combo (mytmouz hit it on the head):