Hollywood1

I have a 1993 z 28 with a 6 speed and I'm thinking about going to one of these gear choices and would like some opinions. I get about 21 mpg and what highway driving I do I don't go much over 65 anyways. My speedo reads about 4 mph higher than actual and at 70 I run about 1600 Rome does this sound about right with stock gears? What gear choice would I be most happy with on performance? Thanks for any opinions.

Austin_Ws6

When I had stock gears I was also at 1600 rpms at 70mph. I went with 4:10s and am more then happy with them. Some say it's too much gear, but I love them.

BLK95-Z

iTrader: (2)

Auto - 373
6 speed - 410

Hollywood1

Thanks...the guy at the speed shop here just told me to go with 410's. Hr said it will feel like an extra 50 Jo.

Hollywood1

Thanks!

Hollywood1

50 horsepower

Blackpanther99

iTrader: (8)

4.10s no doubt.

Tom94TA

The '93 M6 T56 had shorter ratios than later T56s. Normally 4.10s are the way to go but you might want to look at the 3.73 or 3.90 ratios.
Plug your info into this gear calculator.
http://f-body.org/gears/

Edit:
I ran some numbers and if you have the 2.97 1st T56, if you go with some 3.73s you will still have a shorter overall final drive ratio than I do with 4.10s. The only exception is 4th gear (1:1), you won't have quite as vigorous acceleration as a car with 4.10s. This is assuming you have 26" tall tires.

Kind of a interesting situation because 3.73s are a stronger gearset than a 3.90 or 4.10. If your future plans include H/C/I you could go with 4.10s and get the same benefit as 4.56s/late T56 combo. I mention this as sometimes I wish I had gone with some 4.30s in the S60. You have more options than the rest of us.....

BIGCHRISS197

I say 4.10's

02ls1gun

4.10s! When I installed them in my car it was a night and day difference.

user_guest3214

If your car is still pretty original, go with 4.10's. If you have removed a ton of weight, go with 3.73's.

I suppose it also depends on how much you like shifting. The higher the gear, the more you will have to shift around town. I had 4.56 and thought it was a joke. 1st gear had a top speed of about 10-15 mph. I think I shifted my KZ250 dirt bike less than I did the car!

trans_am7935

iTrader: (15)

actual top speed in 1st is ~42 mph with stock red line. top speed in second is just about 65mph. So you wont shift to much, but will definitely shift more when driving around town. considering you dont red line it everywhere. but highway is great with a crusing speed of 65mph under 1800rpm's

Hollywood1

Thanks for all the great feedback...I think 410's will be the best choice for what I'm wanting. Thanks!

Hollywood1

Thanks!

Tom94TA

You do understand that your car with 4.10s will behave the same way as if all these other guys (who are recommending 4.10s) cars had 4.56 gears. It's not a apple to apple comparison.

YOUR speed in gear @5700 with 4.10s
1st 36
2nd 51
3rd 74
4th 106
5th and 6th too fast to worry about
6th at 65 mph is 2200 rpm.

It only gets worse if you have the T56 with a 3.36 1st instead of the 2.97 1st.
The ratios in the '94 and later T56 are:
2.66 vs yours 2.97
1.78 vs 2.07
1.30 vs 1.43
1.0 vs 1.0
.74 vs .80
.50 vs .62

I just don't want you to make a expensive mistake you'll regret.

Tom

user_guest3214

When I had 4.56 gears, you could start out in 3rd gear without any problem. No need to rev the engine. Just let out the clutch and it would go. 1st and 2nd gear were worthless. Using those 2 gears was like shifting a tractor. 6th gear cruised at 2200 RPM at 70 mph. I put in 3.73 now and what a difference! I can actually accelerate in 1st gear!

I had a Mustang SVO with a 3.35 first and 4.10 gears. Too much shifting in the city for me.

Tom94TA

^^^Nevermind, I don't doubt it. Most guys that use 4.56s are running 28" tall slicks at the track and even then their overall ratio is the same as the 4.10/26" tire combo ('94 later T56). Having a wide or close ratio transmission is a huge part of selecting rear end gears. Back in the day I had a 5.0 notch and the recommended gears for that were 3.73s.

user_guest3214

At National Drivetrain, you can buy Motive gears for that axle for $160 on up. Pretty cheap if you put the wrong gear in to switch it for something else. Hopefully he has the right differential so he doesn't have to buy another one to fit the gear.

Austin_Ws6

I think it comes down to how much you like shifting in town. I've had 4:10 cars for about 2 years now and love them.

redbird555

iTrader: (14)

First off man before you go buying gears go look at your option tag. 1993 is an odd ball and come with different rear and trans ratios than any other year. M28 means you have the early t56 which means you actually have a 3.36 first gear, m29 on the door code means you get 2.97.

If you have 2.97 that means you have 3.23 gears in your rear currently and I would recommend 3.73's. 4.10's would be ok but they would be a little short especially for the lower power band of an lt1.

Next if you have the m28 option def do not go 4.10's 1st gear will be non-existent. In that case 3.73's are your best bet again. I dont mean to offend the guys on here but most people look and see t56 and automatically think 4.10s. They dont realize that in 1993 the rear gears in fbodys and t56's were completely different so that logic gets tossed out the window very fast. The eveidence of this thought is right here in the thread, where everybody jumps on the 4.10 band wagon assuming the OP has a normal t56.