differential advice requested
Thread Starter
Burning Brakes
Joined: Oct 2011
Posts: 956
Likes: 86
From: McDonough Georgia
differential advice requested
I have an 81 I dropped a 380 hp, 383 into with a Super T-10 4 speed.
I still have the stock automatic differential in place and want to rebuild the entire rear this winter.
I have the stock 2.87 ratio in the automatic. It spins the tires in low easily and cruises around 2100 rpm on the highway.
I am thinking I should go with 3.5 for better acceleration, but not sure.
Also, can I put in a cast iron diff from a 79 or earlier?
I have read that the aluminum cased 80-82 danas' are not as strong with higher horsepower than 200.
Any and all advice appreciated.
Many thanks
I still have the stock automatic differential in place and want to rebuild the entire rear this winter.
I have the stock 2.87 ratio in the automatic. It spins the tires in low easily and cruises around 2100 rpm on the highway.
I am thinking I should go with 3.5 for better acceleration, but not sure.
Also, can I put in a cast iron diff from a 79 or earlier?
I have read that the aluminum cased 80-82 danas' are not as strong with higher horsepower than 200.
Any and all advice appreciated.
Many thanks
Racer
Joined: Jul 2008
Posts: 338
Likes: 4
From: Bowling Green Kentucky
You would be surprised at what a properly built aluminum take.
My experience is that they are stronger than most think.
Have the carrier set up with a steel cap on the left side of the carrier when doing the gear swap.
Also, step up the half shafts to the manual (1350 u-joints).
Everything in the rear (from the pinion yoke to the spindle flange) must be assessed as well to ensure it is up to par.
There is more to making the rear live than just the differential.
My experience is that they are stronger than most think.
Have the carrier set up with a steel cap on the left side of the carrier when doing the gear swap.
Also, step up the half shafts to the manual (1350 u-joints).
Everything in the rear (from the pinion yoke to the spindle flange) must be assessed as well to ensure it is up to par.
There is more to making the rear live than just the differential.
Last edited by HBZ_81_C3; Nov 24, 2013 at 12:42 PM.
Burning Brakes
Joined: Sep 2012
Posts: 818
Likes: 0
From: coon rapids mn
tracdogg sells the steel cap for the dana rear diff .I would like to retain my dana 44 ,but if I ever brake it ,I will install a steel differential.also be concerned about your half shafts ,get HD half shafts with the better U-joints .
Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Pro
Joined: Dec 2006
Posts: 695
Likes: 5
From: tx
The Vette diff's actually suck. They weren't designed for any real horsepower. GM used lightweight materials and craftsmanship was shoddy - as you would expect from an OEM.
Contact Tracdogg2 on the forum. He is in the DFW area. He set-up mine diff and I am very pleased.
Contact Tracdogg2 on the forum. He is in the DFW area. He set-up mine diff and I am very pleased.
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Melting Slicks
Joined: Jun 2003
Posts: 2,802
Likes: 241
From: Niles, MI
Melting Slicks
Joined: Mar 2008
Posts: 2,666
Likes: 289
From: Spring Park MN
I am one who thinks the aluminum differential is a lot stronger than given credit. I was not easy on the one in my 80 and it served me well.
Thread Starter
Burning Brakes
Joined: Oct 2011
Posts: 956
Likes: 86
From: McDonough Georgia
I am concerned to a degree. The car is an honest 380hp.
I don't race it at all, but do like to get on it a bit. I was surprised how easy it will spin the tires with the gearing for the automatic.
I do have to get the revs up in 1st.
Think I will keep the aluminum case and go with3.54 and contact traccdog.
I don't race it at all, but do like to get on it a bit. I was surprised how easy it will spin the tires with the gearing for the automatic.
I do have to get the revs up in 1st.
Think I will keep the aluminum case and go with3.54 and contact traccdog.
Last edited by commander_47; Nov 25, 2013 at 01:42 PM.
Drifting
Joined: Jul 2002
Posts: 1,995
Likes: 110
From: Garland Texas
Commander: You may be happier with 3.31 gears unless you're planning to upgrade to an OD.
Mike
Advanced
Joined: Nov 2002
Posts: 58
Likes: 0
From: Mill Hall PA
The aluminum Dana 44 is better than many people give it credit for. After all, it is a Dana. The internals are still cast iron and steel. I've built a few for autocross; one with a 3.54 and another with a 3.73 with no problem. Dana differentials are not simple to setup, but any Jeep, Ford or Corvette expert should be able to build one to last.
The steel main cap sounds like a good idea for massive power. More of a concern is the size of the u-joints in the halfshafts. In an automatic tranmission vehicle the u-joints are smaller than a manual transmission vehicle. The larger output shafts will fit any Corvette Dana 44. I converted two of them already. Also needed are the larger halfshafts and trailing arm yokes. I installed Moroso bearing caps on each u-joint with 3/8" nut and bolt to replace the small retaining strap and 1/4" torx bolt.
The steel main cap sounds like a good idea for massive power. More of a concern is the size of the u-joints in the halfshafts. In an automatic tranmission vehicle the u-joints are smaller than a manual transmission vehicle. The larger output shafts will fit any Corvette Dana 44. I converted two of them already. Also needed are the larger halfshafts and trailing arm yokes. I installed Moroso bearing caps on each u-joint with 3/8" nut and bolt to replace the small retaining strap and 1/4" torx bolt.
Last edited by jcuprisi; Nov 25, 2013 at 07:14 PM.