G body rear end swap options...F Body?

[MrSony]

Hey guys. I saw a 10 bolt posi 7.5 rear for 150$ on my local craigslist, and unfortunately I was too late to get it. Then I was wondering if a 3rd or 4th gen f body rear end or one from an s10 would bolt right in. I would take out the carriers, but I'd rather have a drop in kinda deal, you know? Any help is appreciated.

 

[pontiacgp]

The S 10 rear end is not the right width to fit a g body, the camaro rear end doesn't work, they have a torque tube instead of upper control arms.

 

[TexasT]

How deep are your pockets and how much power do you intend to put down?

http://www.quickperformance.com/9-Ford-Complete-Rearend-GM-G-Body-78-87_p_20384.html

This is where I am headed when I break the 8.5 in my car.

 

[ssn696]

The Gbody uses a four-link rear control arm setup. The upper bushings are centered over the axle tube centerline. The later-model Caprice rear and 64-72 Chevelle axles are wider and the upper bushings are centered slightly forward of the axle tube centerline, so they are not bolt-in. I have heard there were special aftermarket upper arms made a while ago to use a Chevelle 12-bolt in a G-body.

The Grand National and Hurst Olds use an 8.5" center section that has the exact G-body control arm mounts, but they are hard to find and often hammered after 30 years. The F-body uses nearly identical lower control arms as a G-body, but instead of upper arms, they use a torque arm that connects to the transmission tailhousing, and panhard bar to locate the axle left-to-right. See PontiacGPs photo. The S-10 uses leaf springs, and there is no easy way to add the upper mounts onto the cast iron center section.

So, keep looking for a GN 8.5 axle. Or keep a spare 7.5 G axle around. Or if your pockets get deeper, go with Ford 9". The reason they are the go-to axle is that they are durable (used under half-ton trucks and under 5500lb Lincoln Continentals). The 9" housing itself is made from formed steel, so it is easy to weld in G-body bushing mounts. Plus 9" axles use pressed-on captured axle bearings, so no C-clips to break and lose a wheel under abuse.

 

[pontiacgp]

The 10 bolt 8.2 or the 12 bolt 64 to 67 Chevelle rear end is 2.5" wider then the G body rear, the 68 to 72 Chevelle rear is 4.5" wider than the G body. The spring perches sit furthr forward than the perches on the G body rear but it doesn't affect the spring. The 64 to 72 Chevelle rear needs the conversion uppers and a Roto Joint at the axle to pick up the angle. The rear end is wider than than the G body rear but the bracket for the lower control arms is closer to the center of the rear axle than the brackets on the G body. The 68 to 72 Chevelle only needs the conversion uppers and the lower control arm from the G body will fit. I use UMI products for the rear of my GP. Here is a picture of my 8.2 rear from a 67 Chevelle to show the angle the Roto Joint is picking up. UMI made the lowers special for me to have the Roto Joint on the axle side of the lower control arm..UMI only charged me the difference of the regular joint and the Roto Joint and did not charge me any of the machining required...

 

[MrSony]

Ok thanks. And yeah, for now at least I plan on barely having 300hp to the ground. But as much as it would be to build that lil 7.5 up to where I want it, I could get a new aftermarket unit complete and drop in. At some point I garuntee I'd want some more power, maybe a turbo V6 or something for my regal. I like the idea of my rear end staying intact no matter what I throw at it. My only concern then would be the crappy 200 metric. That 9" looks very appealing though. It'd take a few months to save, but I could swing it.

 

[MrSony]

BUT I also do live near and know a bunch of old racers and current racers who have g bodies and ford 9"s they've modified. I could pick up a decent one for fairly cheap, have it gone through, and put some sensible gears in it.

 

[lilbowtie]

Detroit area Craigslist $150.00 for all of it.