To anybody that has installed a new set of gears and posi, I'm looking for comments. I'm considering getting a set of 3.73's to replace my 3.27's and I'm wondering what everyones experience was with them...gas mileage, RPM on the highway, city driving, at the track improvements?!?

 

Do NOT run 3.73's with tpi

Thats my experience/comment.

I've ran a few different gears, my favorite is by far 3.42's


3.73s are fun launching, but the fun ends soon.

 

eventhough I haven't tried any other gear than my stock 3.27's, I have to agree with tpi_roc. I'm thinking of going to 3.73s only AFTER I do the LT1 intake swap..

 

I agree ,I have them and they are a little too steep,even with 28 in tall tires im still going through the lights a little over 5000.From what I've seen and read,it also zips through the torque range way too quick.Most of the fast TPI cars are running 3:42's,sure wish thats what i had put in when I shelled the rear last summer

 

Jumping on the 3.42 wagon here, thats what i have(I Love it!). I bought an 8.5 rear end out of a Hurst Olds for my Monte SS but it has 3.73 gears and that is too steep for my TPI so, i will be having that rear rebuilt with 3.42's like the Buick Grand Nationals.

 

I have to disagree on the 3.42 chioce. I have run both and prefer the 3.73's. At 85 mph, i'm only turning 3000 r's and they give on helluva launch at the track. Speaking of track, I trip the lights at an alt. corr 13.90 @ 94 mph, 4800 rpms.

It is all about choice. The 3.42's are very good gears, but the 3.73's don't hurt on the top end as percieved.

Lates,
JD

 

If the car sees daily interstate time, you will soon hate 3.73 gears.
The 3.42 is a good general purpose gear. 3.73's are for engines
that live on the wilder side of life and easily pull to 7K.

 

I just swapped from 2.73 to 3.42, I love it !!

John