C body rear end swap into b body

[nigel]

hey guys. So my car is currently a 318 car with a 904 and an 8.25 rear. The motor is cracked so I found a donor c body that will give its heart to make my satellite live on. It’s a 66 New Yorker and it’s a low mile car. Only 48k on the car but it sat outside all of its life so it has rotted away. The motor and trans are sweet as a nut so I will transfer them into the satellite. I will be changing torsion bars and the rear leaf springs for more adequate ones.
Now what I want to know is how can I get the c body rear into the b body? I know I have to get the pinion angle changed and move the leaf spring mounts. How about narrowing? Will it have to be done or would I get away without doing it?

 

[beanhead]

You didn't say what year your car is, check this thread from FABO.
https://www.forabodiesonly.com/mopar/threads/an-accurate-8-3-4-rear-axle-width-list.365494/
I've found it to be accurate.. depending on what kind of wheel and tire you want to run, get the rim backspacing that locates the wheel where you want it.

 

[Lefty71]

Just today ran into what I assume is an 8.25 in a C-body, but I assume you are saying you got an 8.75 from an older C-body?

 

[nigel]

Sorry guys. Left out one of the most important parts. The doner car is a a 66 new yorker and it's going into a 69 satellite which currently has an 8.25 in it and yes the c body doner has an 8.75 rear

 

[Lefty71]

Looks like a smidgen under 2" difference in the housing. Cut it down, and buy some custom axles from a high strength supplier like Strange and you are golden. They don't cost too much.

 

[nigel]

They don't cost too much in America but with importing into ireland it's like having to buy the same part twice with the amount of tax and duty I have to pay

 

[Lefty71]

Move here, lol (you are welcome)

 

[nigel]

Move here, lol (you are welcome)

I did live there for about five years. Best time ever. Spent my time in north Alabama. Wish I could move there but work has me stuck here in ireland. We always laugh at how much money we spend here in ireland with our cars and depress ourselves thinking about what car we could have if we lived there

 

[Curiousyellow71]

If the tire are only out 3/4"on each side I would just put it in....cut the C body spring perches off and match them up for your cars springs..you will hardly notice. The front track width on 69's is wider then the stock rear track width...the rear end will match up better in that regard.
The only time you will notice the wider rear end is if your trying to fit the biggest tire in the wheel well you can fit...even then it's not a big deal...they make aftermarket rims with different back spacings.

 

[beanhead]

You can do it with the rims. For example...a '69 8-3/4 will have the wheel mounting surface centered, or very close to centered, in the wheel well. If you were using 8" wheels, a 4" backspace would then center the wheel and tire. So, if the 'C' rear is 1" wider on each side, a 5" backspace would put the wheel in the same spot. If you're going with a 7" wheel, 4" backspace will be fine.

 

[nigel]

Awesome. So looks like there is a chance i will get away with it. I have aftermarket wheels that came on the car. I will have to do some measuring on the backspace and see how i get on. As for the spring perches im a welder anyway so i can take care of that. Just send my driveshaft out to get shortened then and instead of spending 2k to get the back end done I can get new springs and hit the road soon

 

[33 IMP]

Easy to adjust for the extra width with backspace adjustment on the wheels. Ive got a 65-67 b body rear in my 62 that is a half inch wider per side (to get away from the early flanged axles). It was there when i bought the car, and i didn't even know. I just used wheels with more backspace, got 10 1/2" slicks under it. I used centerline autodrags with 4 7/8 bs. 15x8 (or 8 1/2, dont remember for sure)

 

[nigel]

I wanted to get myself a new set of wheels buy I couldn't afford it because of the work I had to do on the rear end. It's great that I can remedy the situation with getting new wheels. I never actually thought about it so cheers everyone. I'll be shopping for a set of weld prostars for the car now