Rear End Swap, which ones work?

[CaliCuttie]

Hey G-Body peeps,
My hours at work have increased, so this means I'll be able to fund summer projects. This summer I wanted to swap rear ends in my '86 Cutlass. Its equipped with a gutless stock 2.14 rear end and would like to know what donor cars would have rear ends that I can use. Granted there's the obvious 3.73s from GNs and 442s, but what options from non-Gbody cars do I have? And are they direct drum to drum installs or am I just swapping the gears that's in the middle (I know little about rear ends by they way, just that higher gear ratio rear ends will give me more torque thus power to the ground and won't take a dump when I decide to drop an olds 350). Alrighty awesome, thank you!
-Mike

 

[JBreu]

Well, if your looking for something other then the G-Body rear ends..go with the A-Body ones then as they will literally bolt in with very lil extras.........such as different upper/lower control arms ........then again I bolted in a 72 elky 12 bolt into my 79 Monte with nothing besides a rear conversion U-Joint, even used my stock 79 gear and had no issues (that I know of). You could also go for a ford 9" rear.........but F that..keep your GM car all GM, JMO of course

 

[Doober]

You can swap just about any factory 4-link GM rear in (A-Body, B-Body), even a 9" or 8.8", but there are some geometry issues with the 8.8"... aftermarket companies make bolt-in 9" rears.

 

[CaliCuttie]

Cool! Maybe I'll swap the 3:55 posi out of my dad's '69 GTO while he's sleeping, I'm sure he won't notice :wink:
That's really really good to know because I definitely see a lot of A-Body rear ends on my craigslist, and nothing that I would want from a G-Body car, any more info on a G-Body to A-Body conversion would be great! Articles, etc

 

[Doober]

Well, many rears that people think are 8.5" under Chevy A-Bodies are actually 8.2". Just be sure of what rear you're looking at before you buy it.
http://www.maliburacing.com/forum/viewt ... 09#p731209

 

[CaliCuttie]

That's a very good resource doober!
I just got off the phone with a guy that has a 3.42 rear from a Regal T-Type, and a 3.73 from a Monte SS. While the 3.42 isn't posi which is the better of the two, and is a 3.73 really going to dog me on gas like my dad is warning me about? Thanks!

 

[Doober]

If you can get the one from the T-Type for a good price I'd say go for it if it's truly an 8.5", you can always change the gears. If you get the 3.73 and it's just a 7.5, it won't be any better than what you already have besides being a different gear ratio. 3.42 to 3.73 probably won't make a huge difference, your biggest change will be going to either of those 3.xx gears from a 2.14.

 

[JBreu]

If you can get the one from the T-Type for a good price I'd say go for it if it's truly an 8.5", you can always change the gears. If you get the 3.73 and it's just a 7.5, it won't be any better than what you already have besides being a different gear ratio. 3.42 to 3.73 probably won't make a huge difference, your biggest change will be going to either of those 3.xx gears from a 2.14.

X2 I'd say scoop that T-Type rear in heartbeat as long as you get a decent price!!

 

[DRIVEN]

FWIW, since your sig lists a 200-4r you really should be fine with either ratio. In my case I found that 3.42s with the overdrive has the equivalent final ratio as a 3 speed with 2.29s. Mess around with this for a few minutes:
http://www.angelfire.com/fl/procrastination/rear.html

 

[dogsht]

Yea Calicutty if you are staying with that 307 or another small block the cheaper 7.5 should be strong enough and the 3.73s will make the most of it. As the calculator will tell you final drive ratio with the 3.73 will still be 2.49 which will still get good mileage on the highway. Naturally if you are going for more power or can get it cheap enough snatch up that 8.5!