1980 Malibu What rearend should I use??

[Young3]

I have a 1980 Malibu and im in the process of going from the stock rearend to either a 8.5 inch or a GM 10 bolt. The thing is, is that the 10 bolt came out of a pontiac formula and I would have to have the housing shortened along with the axels. Then I would need a mounting kit, and have the brakets welded. I would be going from a drum to a disc rearend. I dont know if im wasting my time or should I just go with the 8.5?? Ive heared both sides, but I was wondering what everybody else thought. I have a 355 with a 350 turbo 3spd transmission pushing roughly 450-490hp with a little shot of nitrous. Let me know what ya think

 

[85 Cutlass Brougham]

What Year Firebird Formula? If it is a second generation F body, it is likely already an 8.5. Starting in 1972 or 73, all F bodies got the 8.5 as the 8.2 and 12 bolt ( 8.875 in) rear axles were phased out.There are several 10 bolt rear ends and not all are the same. The 8.5 is the best one, the 7.5 is the worst. The 8.5 G body rear axle is very hard to find, but is a bolt in. No F body rear axle bolts in to a G body because they use different suspension-either leaf spring from 1967-81, or a VERY different 4 link from 1982-2003. From 1982-2003, 3 different rear axles were used. The 7.5, 7.625(same as 7.5 but with 1/8 in more ring gear) and Australian 9 bolt which is found only in some 350 powered late 3rd gen F bodies. You could also consider a Ford 9 inch as housings are available that make it a bolt in to a G body, but it can get pricey unless you stay with the basics.

 

[scottco]

I have a 80 lemans and i went with the ford 9",4 link.works awesome.

 

[Powerhouse]

http://www.powerhouseperformance.ca

Can hook you up with either a 12 Bolt bolt-in or 9" Bolt-in...

By the time you shorten, re-weld, cut the axles... you may as well just get one the bolts in.

I'm got a Moser 9" in mine it's awesome

 

[bowtie81]

rear end

you could go with a 12 bolt out of a 66 chevelle and it bolts right in, just have to get a set of rims with a back spacing of 5.5 inches. thats what i had to do

 

[Tony_SS]

Re: rear end

you could go with a 12 bolt out of a 66 chevelle and it bolts right in, just have to get a set of rims with a back spacing of 5.5 inches. thats what i had to do

x2. they even make the upper and lower control arms for the g-body swap.

 

[80' bu]

Can hook you up with either a 12 Bolt bolt-in or 9" Bolt-in...

By the time you shorten, re-weld, cut the axles... you may as well just get one the bolts in.

I'm got a Moser 9" in mine it's awesome

Whats the price for a complete 12bolt?