rear end ratios
Thread Starter
Race Director
Joined: Sep 2005
Posts: 13,269
Likes: 0
From: Sharpsburg Georgia
GA Events Coordinator
rear end ratios
I am thinking about changing my ring and pinion in my 87 coupe, it is a stock auto with a procharger and intercooler.
Does anybody have any suggestion on ratios? i would think that a 3.54 would be as high as i wanted to go, and that might be to high?
In looking over the repair manual it is calling for a carrier spreader, and several other special tools, is this really required?
i do have the tools to set the depth and backlash and have done a few rear ends before, just never have done a Danna 36 before.
How bad a hit am i going to take on mileage if i do go to a 3.54? it has a 2.59 in it now.
Does anybody have any suggestion on ratios? i would think that a 3.54 would be as high as i wanted to go, and that might be to high?
In looking over the repair manual it is calling for a carrier spreader, and several other special tools, is this really required?
i do have the tools to set the depth and backlash and have done a few rear ends before, just never have done a Danna 36 before.
How bad a hit am i going to take on mileage if i do go to a 3.54? it has a 2.59 in it now.
Instructor
Joined: Aug 2005
Posts: 105
Likes: 0
From: Nipomo CA
Originally Posted by blown87
it is a stock auto with a procharger and intercooler.
a 3.07 is a nice jump. probobly your best bet with a supercharged car if its very mild i.e:stock cam/heads/intake.
2.59's are for people who like topspeed and do interstate traveling and need decent mileage.
3.31's are probobly not gonna come around since in 84 there where only 410 cars ever made with that special ratio.
3.54's will be probobly too much. probobly won't have traction whatsoever and for a very narrow powerband they just won't cut it very well. 1/8th mile ET times would get better but after that it probobly won't do the car any justice.
Team Owner
Joined: Sep 2001
Posts: 62,157
Likes: 1,731
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
I would look for a 3.07 in a D44 carrier.
3.07s and 3.31s from other automatics are for the 3-series carrier, you have a 2-series carrier.
Nearly all aftermarket manufacturers who make 3.54s/3.73s for the D36 are making them for the 2-series. It would probably be too much for an L98 with SC on top, you'd have no traction.
3.07s and 3.31s from other automatics are for the 3-series carrier, you have a 2-series carrier.
Nearly all aftermarket manufacturers who make 3.54s/3.73s for the D36 are making them for the 2-series. It would probably be too much for an L98 with SC on top, you'd have no traction.
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
How positive are u that u have 2.59 ratio? pl make sure that.
The reason iam saying i was thinking my 85 auto vette has a 2.73 ratio but it end up being a 3.07 and i changed to 3.54 dana 36, dman i would have gone to 3.73 i did not see much diff going from 3.07 to 3.54.
If its ur's a 3.07 (which i believe i might be wrong but u have to make sure) i would suggest going to dana 36 3.73.
Tpis sells them in 3.73 ring and pinion and let it installed by lamar walden in doraville, buford hwy 770-449-0315 atlanta.
Tpis also sells drive and driven gears for ur speedo correction or ask CFI-EFI for speedo related issue.
Dana 44 cost money more than 1200 bucks easily.
The reason iam saying i was thinking my 85 auto vette has a 2.73 ratio but it end up being a 3.07 and i changed to 3.54 dana 36, dman i would have gone to 3.73 i did not see much diff going from 3.07 to 3.54.
If its ur's a 3.07 (which i believe i might be wrong but u have to make sure) i would suggest going to dana 36 3.73.
Tpis sells them in 3.73 ring and pinion and let it installed by lamar walden in doraville, buford hwy 770-449-0315 atlanta.
Tpis also sells drive and driven gears for ur speedo correction or ask CFI-EFI for speedo related issue.
Dana 44 cost money more than 1200 bucks easily.
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Originally Posted by vader86
3.07s and 3.31s from other automatics are for the 3-series carrier, you have a 2-series carrier.
Nearly all aftermarket manufacturers who make 3.54s/3.73s for the D36 are making them for the 2-series. It would probably be too much for an L98 with SC on top, you'd have no traction.
Nearly all aftermarket manufacturers who make 3.54s/3.73s for the D36 are making them for the 2-series. It would probably be too much for an L98 with SC on top, you'd have no traction.
RACE ON!!!
Thread Starter
Race Director
Joined: Sep 2005
Posts: 13,269
Likes: 0
From: Sharpsburg Georgia
GA Events Coordinator
Thanks for your input guys, i am going from the rpo codes to tell if it is a 2.59 "gm1".
How much trouble is it to change to the 44? i am considering this, not real sure how the 36 will hold up when i go for more power, so that might be prudent to go ahead and change it over to a 44.
Vader86, i thank you for the effort you put into you home page, LOTS of good info there.
I need to do the work myself, i own a shop that does mostly European cars. i would have a hard time if i paid some one else to do the ring and pinion for me, plus i still enjoy doing the work myself. (if anyone needs any help with there cars that are made in Europe, i will try to help)
in writting this response, i guess i have decided to go ahead, save my change and spring for a danna 44, i do plan on building at least a 383 when this motor goes bad (not long i fear) with a 3.07
How much trouble is it to change to the 44? i am considering this, not real sure how the 36 will hold up when i go for more power, so that might be prudent to go ahead and change it over to a 44.
Vader86, i thank you for the effort you put into you home page, LOTS of good info there.
I need to do the work myself, i own a shop that does mostly European cars. i would have a hard time if i paid some one else to do the ring and pinion for me, plus i still enjoy doing the work myself. (if anyone needs any help with there cars that are made in Europe, i will try to help)
in writting this response, i guess i have decided to go ahead, save my change and spring for a danna 44, i do plan on building at least a 383 when this motor goes bad (not long i fear) with a 3.07
Le Mans Master
Joined: May 2000
Posts: 7,033
Likes: 12
If you own a shop with a lift I would think you could pull the 36 and install the 44 in under 3 hours.
I pulled 2-36's and swapped them back in the 2 cars, the total job was right around 4 hours. It really isn't that hard to pull these rearends out.
I pulled 2-36's and swapped them back in the 2 cars, the total job was right around 4 hours. It really isn't that hard to pull these rearends out.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Thread Starter
Race Director
Joined: Sep 2005
Posts: 13,269
Likes: 0
From: Sharpsburg Georgia
GA Events Coordinator
Originally Posted by hippy
If you own a shop with a lift I would think you could pull the 36 and install the 44 in under 3 hours.
I pulled 2-36's and swapped them back in the 2 cars, the total job was right around 4 hours. It really isn't that hard to pull these rearends out.
I pulled 2-36's and swapped them back in the 2 cars, the total job was right around 4 hours. It really isn't that hard to pull these rearends out.
What all do i need, the housing, batwings, beam? does this require a drive shaft swap?
Safety Car
Joined: Apr 2003
Posts: 3,793
Likes: 9
From: VA
Originally Posted by blown87
What all do i need, the housing, batwings, beam? does this require a drive shaft swap?
It's no biggie without a lift either.
Thread Starter
Race Director
Joined: Sep 2005
Posts: 13,269
Likes: 0
From: Sharpsburg Georgia
GA Events Coordinator
Originally Posted by steve9899
Safety Car
Joined: Apr 2001
Posts: 3,525
Likes: 2
From: Houston TX
Blown 87,
I had the same motor/car you run in another one of my cars but a convertible, so it had 2.73s. Coupes came with 2.59s with the auto or an optional 3.07. Manual cars came with the 3.08 gears. All auto cars were D36, while manual cars were D44.
That same combo: S/C 350 ci auto, basically stock, works well with either a 3.08D44 or a 3.33D44. I would not suggest any taller, as you should have the grunt to easily pull these gears.
For a blown manual car (4+3), I would recommend the 3.54s, while a ZF works well with 3.45s or 3.73s.
The swap to the D44 is very straightforward (batwing, chunk, driveshaft, and ladder). I have the complete D44, if and when you are ready).
Aaron
I had the same motor/car you run in another one of my cars but a convertible, so it had 2.73s. Coupes came with 2.59s with the auto or an optional 3.07. Manual cars came with the 3.08 gears. All auto cars were D36, while manual cars were D44.
That same combo: S/C 350 ci auto, basically stock, works well with either a 3.08D44 or a 3.33D44. I would not suggest any taller, as you should have the grunt to easily pull these gears.
For a blown manual car (4+3), I would recommend the 3.54s, while a ZF works well with 3.45s or 3.73s.
The swap to the D44 is very straightforward (batwing, chunk, driveshaft, and ladder). I have the complete D44, if and when you are ready).
Aaron
