cristian1311

i have a 93 z28, 6 speed. 383 stroker with several bolt ons. i was wondering what gears to put into it. i was told to put 3.73 and then i was told about 4.11s. can somebody please tell me which would be better? I'm looking to do some races every once in a while but i don't wanna be on the freeway with the car vibrating. thank you

Injuneer

People with the 1994-2002 6-speed manual usually opt for the 4.10 gears. But there is a difference between the 1994-2002 T56 trans and the 1993 T56 trans that will affect the choice of gears. THIS ASSUMES YOUR 1993 STILL HAS THE 1993 VERSION OF A T56 IN IT.

The 1994-2002 T56 has the following gear ratios:

1994 Manual/MN6
1 - 2.66
2 - 1.78
3 - 1.30
4 - 1.00
5 - 0.74
6 - 0.50

All 1994-2002 6-speed cam with 3.42 (GU6) rear axle ratio.

1993 had two T56's available. Which one you have can be determined from the Service Parts label in the glovebox, drivers door or in the console. It shows the options (RPO) that were installed at the factory. You need to see if your label has "M28" or "M29".

These are the specs for those two versions of the T56:

1993 M28
1 - 3.36
2 - 2.07
3 - 1.35
4 - 1.00
5 - 0.80
6 - 0.62

Rear Axle: 2.73 (GU2)


1993 M29
1 - 2.97
2 - 2.07
3 - 1.43
4 - 1.00
5 - 0.80
6 - 0.62

Rear Axle: 3.23 (GU5)

From the above, if you use the 4.10's with the M28, you will have a very short 1st gear, and high revs in 6th gear. With the M28, to get the same overall 1st gear ratio as the 94+ trans with 4.10's (2.66 x 4.10 = 10.9), you would use 3.23's (3.36 x 3.23 = 10.9) or for a little bump 3.42's (3.36 x 3.42 = 11.5).


With the M29, to get the same overall 1st gear ratio as the 94+ trans with 4.10's (2.66 x 4.10 = 10.9), you would use 3.73's (2.97 x 3.73 = 11.1) or for a little bump 3.90's (2.97 x 3.90 = 11.6).