Help choosing gear setup with th400?
Thread Starter
On The Tree
Joined: Mar 2006
Posts: 118
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Help choosing gear setup with th400? I have a th400 in my 00 Z28 with a 28" tire and stock 3.23 gear. I was going to wait to change the gear until the rear goes, but the car just doesn't feel nearly as powerful since the trans swap and the new tires so I'd like to change the gears now since the rear seems to be going strong still. This is currently a bolt on car but I will be adding some nitrous soon. I'm assuming the tire diameter change changed my effective gear ratio to a low 3.XX or even high 2.XX : 1. Before the swap I was going to do the 3.73s in the rear but now with the larger tires I'm thinking more around a 3.90 may be the way to go? Just looking for some advice/opinions from people with similar setups to give me something to go off of before I make my decision. Currently the car is a "daily driver" but I don't drive more than a few low speed city miles each day and gas mileage isn't a huge concern. The car sees the highway maybe once a week for short trips at most.
Joined: Mar 2005
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From: 32639 Groesbeck HWY. Fraser MI 48026
3.73 gears with a 28" tall tire will put you around 2500rpm at 60mph depending on which converter you are running. Also remember the first gear in a T400 is 2.48 and the 4L60 is 3.06 so you are feeling the effects of the slower take off.
