[mpotito]

I listened to the experts at ERA based on my intennded use which is primairly street use. The motor will put out about 500 horse with about 500 ft lbs of torgue at 3500rpm. I went with a 5 speed Richmond and a 2.88 differential gear. At 1000 rpm the set up goes 8.5 mph in 1st, 13.1 in 2nd, 17.8 in 3rd, 22.7 in 4th and 27.9 in 5th. Ratios: 1st 3.27:1, 2nd 2.13:1, 3rd 1.57:1, 4th 1.23:1, 5th 1:1. With a 3:31 differential gear at 1000 rpm: 7.4 mph in 1st, 11.4 in 2nd, 15.5 in 3rd, 19.7 in 4th and 24.2 in 5th.

A Tremec 3550/TKO 5 speed with a 331 differential gear at 1000 rpm does 7.4 mph in 1st, 12.3 in 2nd, 18.1 in 3rd, 24.3 in 4th and 35.7 in 5th. Raios, 1st 3.27:1, 2nd 1.98:1, 3rd 1.34:1, 4th 1:1, 5th .68:1. Using a 377 differential gear at 100 rpm 1st 6.5 mph, 2nd 10.8 mph, 3rd 15.9 mph, 4th 21.3 mph and 5th 31.3 mph.

Hope this helps with your decision.