I have a 9" truck differential that i want to install into a 1980 mustang.
The problem is the 9" diff is about 5" larger than the stock 1980 mustang. I want to cut the housing 2.5" on both ends.

My questionsss : 1.If i cut my housing can i modify my 2 shafts ? 2. Did the end are smaler so the machinist can not make new spline ? 3. look for a 9" same lenght if possible? i dont know the 9" witdh available. Any one can help me please i'm lost. thanks Serge.

 

I believe the axles have straight shafts and can be cut and resplined if needed. Pull them and check.

Bigger question - what are you going to do about the control arms? There aren't any mounting points on the top of the 9".

 

I think that is a popular swap, but unlike '05 & up, they don't show a ready made, just a kit:

Currie Enterprises Racing Rear End Categories

As for axles, you can probably just buy axles the proper length if you narrow your housing to a "standard" width.

31 spline axles will probably re-spline, 28s no.

Are you going to use the truck brakes?

Another (high dollar) solution:

http://www.moserengineering.com/hous...rt-number.html

 

Bigger question - what are you going to do about the control arms? There aren't any mounting points on the top of the 9".[/QUOTE]

I'm gona remove from the 8.8 and weld them to the 9"

 

Can't just build the 8.8 to suite? There are cars in the 8's with 8.8's.

 

They DO have a bolt in for the Fox Mustang:

Currie Enterprises Crate Rear End Products

8.8 stuff:

Currie Enterprises All 8.8 Inch Ford

1979-1993 Mustang Limited Slip Differentials at AmericanMuscle.com - Free Shipping!

Don't the new ones with 400+ HP still use 8.8s? The Shelby with what are they up to now, 850 horse.....an 8.8?

 

If you're going to all that trouble to modify a 9" to fit under a Mustang, why not take it a step further and install a suspension that actually works:

https://picasaweb.google.com/1155523...RearSuspension

I used parts made by a company that is now out of business. But there are other companies that still make non-binding rear suspensions for the Fox Mustang. Griggs Racing has some good parts.