It may not help much to go to a lower gear, for the simple reason that right now your total gear ratio
in low is 11.28 to 1. Your total gear ratio in
low gear, if you were running a powerglide and a 4.88 in your rearend, would be a 8.59 to 1. If you went to a 4.56 rearend gear your total ratio in
first gear would be only be 12.52 to 1. This is one advantage to running a turbo 400 over a powerglide, especially in a heavy car.
Going lower on your rearend gear will pick you up a little but you'll have to decide if it justifies the means, or expense. Just the few things to think about before you spend the moneys to upgrade your rearend.
Originally Posted by nova2206
I have a 3550 lb 67 Chevelle with a 477 iron headed big block with a 400th tranny. It currently has a 1/4 mile set up with a 4.10 gear, tire are 12.50s, it runs damn good in the 1/8th at 6.26 or 6.27 in the heat with a 1.38 60 ft.. I never race a 1/4 mile so what is the right 1/8th mile gear.. I go into high gear about 2 car lengths from finish line.