rear end
Thread Starter
Intermediate
Joined: Aug 2014
Posts: 35
Likes: 3
From: independence missouri
rear end
I have a 91 corvette convertible with the standard (I believe 2.73) rear end. This seems extremely high geared and the power is not near what I expect, it is actually more sluggish on the lower end than my 85. I am thinking of going to a 3xx rear end. Can anyone recommend a gear ratio and any idea why the factory rear end is so high other than fuel mileage?
Team Owner
Joined: Sep 2003
Posts: 25,361
Likes: 2,729
I have a 91 corvette convertible with the standard (I believe 2.73) rear end. This seems extremely high geared and the power is not near what I expect, it is actually more sluggish on the lower end than my 85. I am thinking of going to a 3xx rear end. Can anyone recommend a gear ratio and any idea why the factory rear end is so high other than fuel mileage?
Your axle ratio choices with the D36 are 3.07, 3.54 and 3.73 - How to get there are dependent on the $$'s you'd like to spend.
You guessed at your 2.73 - you might want to confirm using the SPID label RPO list.
Melting Slicks
Joined: Jan 2009
Posts: 3,181
Likes: 286
From: Puyallup Washington
I had a 91 with the 2.73 so I understand what you are talking about. I know there is quite a lot of difference between a 1992 with a 2.73 and a 3.07, which is why I looked for a 3.07 when I bought my 1992. It definitely made the car livelier, compared with a 2.73.
Racer
Joined: Mar 2015
Posts: 492
Likes: 40
From: SE Ohio
St. Jude Donor '16-'17-'18,'19
I don't know what the standard ratio is but there should be a tag on the diff. that says what it is. The window sticker for my 91 shows that it has the performance axle ratio ( a $22.00 charge ). The build sheet has G44 code for a 3.07 ratio and it also has G92 code for performance axles. You may want to check to see if you have to change the axle with the diff.
FYI if you change to a 3.07 the speedometer gear on my build sheet is 42GRN 92.
PA
FYI if you change to a 3.07 the speedometer gear on my build sheet is 42GRN 92.
PA
Thread Starter
Intermediate
Joined: Aug 2014
Posts: 35
Likes: 3
From: independence missouri
Thanks for all the responses.
Team Owner
Joined: Sep 2003
Posts: 25,361
Likes: 2,729
This thread post 4 or 5. Take your pick. You do need to confirm your present ratio "FIRST"
https://www.corvetteforum.com/forums...ing-3-73s.html
