• Hello Guest, welcome to the initial stages of our new platform!
    You can find some additional information about where we are in the process of migrating the board and setting up our new software here

    Thank you for being a part of our community!

V8 final drive ratio

BeaverMeat

Active member
Joined
Aug 8, 2020
Location
Vancouver Island
What final ratio are you guys using with V8 swaps?

Right now my 5.0/T-5 has 3.73s and I find first gear way too short for my liking. It has to do with the '89 Mustang T-5 ratios that are meant for the 3.08 final gears.

I'm wanting to go with a 3.31.
 
I owned a 1988 744 with a Converse conversion and T5 transmission for about three years. Originally the car had a 3.73 ratio open rear end. I installed a 1041 3.31 ratio complete rear axle from a 1992-94 965. I was very pleased with the ratio and the limited slip.
 
Good to know.

Finding a 1030 3.31 axel or gear set will be a bit tough to find in Canada. I guess if I’m going with a Detroit TruTrac I might as well source a 3.31 gear set and be prepared to pay.
 
Depends what you’re doing.
Just a cruiser? 3.31 would be a good choice.
I have 3.73 in the drift car, and will be trying out a 3.31 here in a bit.
 
I will say, highway driving with the 3.73 rear end is pretty annoying. Blowing the tires off at 50-60 is fun though .
 
I will say, highway driving with the 3.73 rear end is pretty annoying. Blowing the tires off at 50-60 is fun though .

Right now it revs around 2000rpm down the highway going 63mph/100km/h... that?s with oversized 205/65r16 tires and a .68 O/D.

Even if I swap to a 3.31 and shrink the tires down to the proper size it will be reving at 1900. I would like it closer to 1500-1700 but I guess you can?t have it all.
 
I'm using a CD009 style Nissan trans on mine (alu 5.3 with a turbo). And those ratios are rather short for a 6 speed:
1st: 3.79
2nd: 2.32
3rd: 1.62
4th: 1.27
5h: 1.00
6th: 0.79
370Z MT rear axle:3.69

So far, as a 'temporary' standing (it's been that way for a year so far, lol) I'm still using my 245's original 3.73 rear axle. Which is actually pretty close to what Nissan uses with the same trans. But... it's pretty ridiculously short, especially for a motor chock full of torque like the 5.3 Ellis.

I have a narrowed Ford 8,8 that I'll put in at some point, I just need to ponder the gear ratio. It will def. go taller. Low 3's.

Spinning the driveshaft slower at higher speeds is a pretty good thing, not much downside.
 
I’m so thankful for this thread. I have been suffering with the factory 3.91 and wondering where to go next.
 
Yeah that t56 0.5 is amazing. I’ve been holding out for one.
 
Here's a nice gear ratio/car speed calculator: https://www.tremec.com/calculadora.php

I'm thinking a 3.08 will work pretty well in my Ford 8.8. The taller the rear axle ratio, the slower the driveshaft turns, which is a good thing if you ever get the car up to high speeds. Just look at what happened under propav8r's donor car. As long as the transmission is suitably geared lower.
 
Last edited:
What is the diameter of your tires? OK, 205/65R-15 tires = 25.49"

205/65r16

26.5"!

Way too tall for me. Looking to step it down to a 205/50r16 or 205/55r16... 225/50r16 would be the cat's-ass but I'll have to check if they'll fit. The ASA AS-1s that are on it now are 16x7 ET18 (haven't been able to see an other set like them online)
 
Last edited:
The 225/50R16 will fit without issue, same size I'm running on a similar wheel.
You will want a 3.31 with that diameter of tire.
What 5th gear ratio does your T5 have?
 
The rare-bear 3.15 '83 3-speed auto 760TD if it's a 6.0 alum LS with most of the trans available with ~.80 OD & stock diameter tires for a street car?.

But probably 3.31s oftentimes from manual EFI 83+ 240s / 92-94 solid axle 965s for you 7/9 solid axle guys of stuff that's cheap/commonly junkyard available?
N/A manual 4-cyl 700s have 3.31s as well, though 92-94 960 are a lot more common...anymore.

3.31s pretty common, 3.15 very rare, 3.54s somewhat rare (manual Diesels, 700 Turbo), some canadian GLT w/B23E/3-speed autotragic if they haven't all been crushed/rusted out/canadian wreckers don't want a million dollars for any one single part/full service only or drive foooorever to a self-serve junkyard where those cars probably aren't (Kelowna or Kamloops?)/all gone by now.
 
Last edited:
Back
Top