12 bolt rear

[502monte]

i just bought a 1984 monte with a 502 big block in it. currently has a turbo 350 trans and a 10 bolt. i plan on drag racing it. the 10 bolt will snap in half with big block power. i read that a chevelle 12 bolt bolts right in. will a 1970 chevelle 12 bolt swap right in? i found one locally with 4:11 gears and a mini spool with hardened axles for a good price but i want to make sure it will fit.

thanks
mike

 

[bowtie81]

hey buddy
Yes it will bolt right in with no problems, you might have to get a different u-joint and the rims, you might need a set that has a backspacing of 5.5 inches. thats if your rims are 15 by 8. i have a 12 bolt out of a 66 chevelle and i had to get rims with that backspacing and the u joints i needed to get 2 of them. one side is a bit longer and the other uses a different style of clip. your parts store should be able to hook you up. mine bolted right in to my 81 malibu

 

[502monte]

thats why i asked. i saw your post about the 66 chevelle 12 bolt and wasnt sure if they were one in the same. what do you mean about the u-joints. i dont quite understand what you were saying

 

[85 Cutlass Brougham]

There are 2 widths of factory 12 bolts used under Chevelles. One is from 1964-1967, the other is for 1968-1972. As far as the U joints go, the Yoke is likely a different cup size and will require that you either use adapter joints or have the driveshaft yoke changed to the 12 Bolt's size.

 

[Tony_SS]

Which one was wider again? I know one is 2" wider.. was it the 68-72's?

 

[85 Cutlass Brougham]

I think the later one is the narrower one, but don't quote me on that. I know there were adapter lower arms offered by Southside Machine a few years ago to put a Chevelle rear in a G body, but don't remember anything else about it.

 

[502monte]

from what i've been told the earlier one, 64-67 is the narrower one. does anyone have a link to these lower control arms im going to need?

 

[N.O.S SS]

The 64 to 67 is the narrower rear,I know cause i have one of each in the garage.Finding those lower control arm`s is a problem since south side machine went out of busniess.If you find a set let me know,i be interested in getting a pair myself.

 

[85MonteCarlo305]

I know where you can get a pair of stock lower arms or upper arms if you want to know.

 

[lester622]

http://cgi.ebay.com/ebaymotors/G-Body-1 ... dZViewItem

Item number: 190141994151

those are the 12 bolt swap arms, u also have to move the shock mounting points and move the spring cups. Heres a picture of mine. click the picture itll make it bigger