Rear end gear ratios: 3.73 3.90 4.10

[91CoupeMike]

So I'm tired of listening to my gears whine and howl and piss me off, so the thought comes to mind to change the gear ratio.

Right now I'm have 3.73s I trap 81.7 in the eighth with 26 inch slicks. I'm right at about 5500rpm in third.

So I have room to gear up if I wanted to run the piss out of third or I could shift into fourth.

So my question is, would shifting into 4th be benifecial? I've tried it at the track, I get the same e/t but .5-.7 mph slower.

I'm thinking 3.73s will be the best, just running it by and getting some second opinions.

Car has a stock motor from 1991 and runs 8.4 at 81.7.

[JC316]

On a 5 speed push rod motor, I would say 3.73's. 4.10's would be too much IMO.

[91CoupeMike]

On a 5 speed push rod motor, I would say 3.73's. 4.10's would be too much IMO.

Thoughts on 3.90?

[pr1042]

Probably just right at 3.73. Dyno could tell but I would imagine your power is gonna start dropping if running 3rd further than you are now.

Everything I've heard about motive 3.90 is that they are noisy. May just be the install though...

[JC316]

Thoughts on 3.90?

None of the cool kids run it. 3.73's is a good gear for the track and for daily gas mileage.

[91CoupeMike]

Probably just right at 3.73. Dyno could tell but I would imagine your power is gonna start dropping if running 3rd further than you are now.

Everything I've heard about motive 3.90 is that they are noisy. May just be the install though...

Dyno on saturday!

I'd say you're spot on, or I'm already taking it to far. I normally shift at about 4800 and Ive seen the best results.

[Trick Pony]

For stock power band 3.73s should be optimal. Otherwise, you can go 4.10s and if the steeper gear helps your 60-ft and you shift into 4th at the right rpm it might shave a couple tenths.

[majorownage]

4.10 for 1/8

[Grape]

6.33 or 6.50

[TEAMJACOB]

I skipped to the bottom to post that I voted for 4.10s. Its all realitive to what you want though.

[Juiced4v]

4.56's

[2cammer97]

3.55's. Maybe i'm getting old.

Marcus

[46Tbird]

Your stock engine will prefer 3.55 or 3.73. The 4.10s are just too much.

If you're going to keep the engine stock I'd say 3.55s. If you're planning to do cam and heads, I'd go 3.73s.

You probably won't have much of an ET change with 3.55s. It may actually be quicker.

[SNEAKY]

3.73

[91CoupeMike]

3.55 was in my line of thoughts as well. Would throw the rpm lower in 3rd, that would probably work better.