D36 3.73
Team Owner
Joined: Aug 2005
Posts: 34,988
Likes: 515
From: Riverside County Southern California
Co-winner 2020 C4 of the Year - Modified
2018 Corvette of Year Finalist
2017 C4 of Year
2016 C7 of Year Finalist
St. Jude Donor '09 thru '20
Some LT1 owners with the A4 find 3.73's work well, but doubt they would be a good choice with a crossfire, even too steep for the L98's due to the torque curve.
I tried the ratio in my 93 with LT1 power and found the high RPM annoying at freeway speed, I have since changed to 3.45.
I believe you will find 3.07 to be a better choice.
I tried the ratio in my 93 with LT1 power and found the high RPM annoying at freeway speed, I have since changed to 3.45.
I believe you will find 3.07 to be a better choice.
The 3.73 is an excellent combo for the ZF tranny.
Burning Brakes
Joined: Apr 2007
Posts: 1,178
Likes: 15
From: Montreal Quebec
i do have a 3.07 A4 stock on my 92 z07 lt1 will i see a big difference if i go to 3.73 and did i have to go to dana44 to go 4.10 any idea witch rpm i will get at 75mph i actually doing 2100rpm what will be the better choice!!! 
what will be the better choice!!!
the zf6 already have a factory 3.45 why change to 3.73 
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
there is a difference you can feel. My conservatively moded '89 (stock tire sizes) with A4 & 3.73 is ~2,200 RPM @ 75 MPH in OD works out to be ~ 20 HWY...only get ~ 12 CITY I've done the 4.10 on another TPI car but would not do it again unless the gears are in a dedicated track car or you are running a much taller rear tire.
Drifting
Joined: Sep 2002
Posts: 1,642
Likes: 0
From: Suwanee,Ga
The question I have to ask is
"do you get a new Speedo" gear for trany when you buy those non-stock gears" "?
The speedometer won't be particularly accurate if you have a 2.59 speedo gear with a 3:65 rear?
TJM
"do you get a new Speedo" gear for trany when you buy those non-stock gears" "?
The speedometer won't be particularly accurate if you have a 2.59 speedo gear with a 3:65 rear?
TJM
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
It's not that hard to swap out the speedo gears at the time of the swap since the C-beam will be out anyway. 4 bolts for the tailshaft and switch gears.
