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1985olds
08-14-2018, 09:06 AM
I'm building an 8.8 for my g body and looking for opinions on gear ratios. Cars weighs 3300, trans gear ratios are; 1st-3.01, 2nd-2.07, 3rd-1.43, 4th-1.00, 5th-0.84, 6th-0.57, engine is an 5.3 making about 400 wheel. Car has 4.10s now, but think it might be quicker with a 3.73 or 3.89. Car spends 95% of its life on the street and the occasional autox. Any thoughts?

65 drop top
08-15-2018, 09:11 PM
What is your rear tire height?

68Formula
08-16-2018, 09:24 AM
Assuming 26" tall tires, the 3.89 rear would be a better match for the 3.01 1st gear off the line, than the 4.10s. And in 6th, you'd still be < 2200rpm @75mph. 3.73s would work well too.

Plus, with either the 3.73s or 3.89s; if you spin it up to 6300, you could actually hit 60mph in the top of 2nd before shifting (for 0 to 60mph bragging rights).

1985olds
08-16-2018, 01:19 PM
Thanks for the replies, sorry I forgot the tire size. It's 25.66" (275/40/17). Good points formula

andrewb70
08-17-2018, 05:48 AM
If it already has 4.10s in it, just run them and see how you like it...

Andrew

1985olds
08-17-2018, 03:01 PM
If it already has 4.10s in it, just run them and see how you like it...

Andrew

The rear I am running now has 4.10s. The new rear is from scratch, I don't have heard yet