8.8 Ford on GM A body....

[csouth]

I haven't been here in a while, but finally getting some funds to get back into my project. So now I want to address the rear end. I'm wondering has anyone used a Ford 8.8 on a GM A body car, mine being 72 Olds? I hear they can be strong enough for my application and cheaper to build than a 9". The PO of my car put an O 12 bolt from a 1969 and posi units are difficult to find. I see 8.8 from a Fox body Mustang is 56.5" from backing plate to backing plate, so I was told this would be a good choice. Any thoughts on how involved it might be? I'm assuming would need new perches and shock mounts to go with the GM lug axles?

[Randy67]

Check the width, the Fox axle is not as wide as the A-body needs. I used to have an 03 Mustang which has a wider axle and it was close to the same width as my 67 El Camino. The 99-04 axle would probably be a better choice. The stock A-body control arms won't work with the Mustang axle though. Lower mounts are easy to change but the mounts on the center section are in the wrong place.

[csouth]

Thanks for the response, I'll have to check my info again. I thought I read the chevelle axle was 56" backing plate to backing plate. I'll measure mine again to be sure. I have a Cutlass, but used it as a reference based on A body. I also have access to an 8.8 from a 96 Mustang GT, not sure of the width on these...

[big gear head]

I have a FOX 8.8 rear end and it's 59 1/2 inches wide over all. Backing plate measurements are useless when doing something like this. You must get the over all width. The '72 Cutlass rear end will be 61 inches wide, so the FOX rear end is just 1 1/2 inches narrower.

You would have to add the spring perches to the axle tubes and change the lower controll arm mounts. You might be able to use some fabricated upper controll arms to work with the Mustang mounts.

Auburn makes a limited slip differential for the O axle, and the Traction Lock was available, but might be discontinued now.

[Thrillrr]

Here's a thread on 8.8 for a g body so I think that may get you in the ballpark.
http://www.maliburacing.com/forum/vi...hp?f=4&t=72070

[csouth]

I have a FOX 8.8 rear end and it's 59 1/2 inches wide over all. Backing plate measurements are useless when doing something like this. You must get the over all width. The '72 Cutlass rear end will be 61 inches wide, so the FOX rear end is just 1 1/2 inches narrower.

You would have to add the spring perches to the axle tubes and change the lower controll arm mounts. You might be able to use some fabricated upper controll arms to work with the Mustang mounts.

Auburn makes a limited slip differential for the O axle, and the Traction Lock was available, but might be discontinued now.

I'm going to check on the Power Trax LSD . I also checked and I believe the Mark Vll rear is the same width 61 at mounting surfaces with rear discs.

[RaiderLSX]

I know I'm bringing this back from the grave but, I have some 4.10's a LSD for a 8.8 that I didn't use for my last car. Has any body done this or figured out what needs to be done to make it work.

[SD455]

Has anybody successfully done this swap? Ford 8.8 into an A body? I see lots into G bodies, but nothing for the more popular A body.

[parsonsj]

I'm putting a Quadralink on an 8.8. They've got 3" axle tubes, so it's easy to cut off the existing brackets and weld on new ones.

[andrewb70]

I'm putting a Quadralink on an 8.8. They've got 3" axle tubes, so it's easy to cut off the existing brackets and weld on new ones.

The issue with using them in the A-bodies is that the upper control arm mounts are cast as part of the differential. The suspension design in a Fox and a A-body (g-body as well) are very similar, but the axle side upper control arm mounts are in the wrong place. After adapting the Fox axle, it might be easier to do a 9".

The 9" has some advantages. First, bolt in axles. Second, the upper mounts are higher making the geometry more desirable. Third, pinion position is lower which tends to improve the driveline issues that come up when a-bodies are lowered.

Andrew

[parsonsj]

Ah. My 8.8 has only the 3 link cast on the top of the center casting. There aren't any ears... just a "hat". I'll mill that off.

[dontlifttoshift]

05-14 mustangs have the three link, all the earlier SRA mustangs had the quadrabind.

Exploder 8.8s have leaf spring pads and measure somewhere between 59 and 60" hub to hub. These are usually the best starting point because cheap, plentiful, and 3:73 or 4:11 stock with a pretty decent posi.

I thought 8.8s were a tad lighter than a 9" and I think they use less power. The best diff next to a Quaife is readily available in the Torsen T2R.

John, make sure to weld the axle tubes, without the 3rd link on the top to help, there is only a pressfit and some plug welds holding it together.

[wiedemab]

Just realized that Donny already said some of this, but......

I have 2 8.8's out of explorers..... 31 spline axles and the only brackets on them that I recall are 2 leaf spring pads - -nothing is cast into the center section. Certain year F150's also used them if you are just looking for something that you are going to have to change the width on anyway.

[parsonsj]

John, make sure to weld the axle tubes, without the 3rd link on the top to help, there is only a pressfit and some plug welds holding it together.

Yes, I see what you mean. It was already in the plan as a "good idea". Now it's been raised to "git 'r done".

[chpr1972]

Just a thought. Why not put a narrower rear end in if they make it without cutting the ends off. Then you can use a less positive offset and have a wide wheel that has a more aggressive look. A wider lip to the wheel center always look more tuff. I have 11" wide wheel on my 66 Lemans conv now and the wheels have a major back spacing 6". A 4" [2" per side] narrower axle would give me a 4" back spacing and still have a 11" wheel.

[Nothingface5384]

Contact monzaz of jdrace.com
he can modify an 8.8 posi unit to fit into a type O
Sucks you didn't have the original bolt in axle 8.5 with 3in axle tubes

[csouth]

Contact monzaz of jdrace.com
he can modify an 8.8 posi unit to fit into a type O
Sucks you didn't have the original bolt in axle 8.5 with 3in axle tubes

As far as my interest goes this thread is long dead. I put a Moser full floater in my car..