B-body rear-end swap into an A-body

[Gospel Runner]

I have just put a 360 into my 70 Dart where a slant 6 225 used to reside. I have a B-body rear that I would like to replace the existing small rear. I kow that it is 3" longer and I must relocate the springs. Do I have to shorten the rear or can it be used as is? Can anyone lead me to a tech article that addresses this issue or give me a step by step approach to this problem? Any help would be greatly appreciated! Thanks from Gospel Runner.

[mopar stu]

it would have to be cut,or use some custom offset wheels.check your measurements again it may be larger than 3" in which case you would have to cut it.I have an 8 3/4 housing for sale for an a-body for $200 too.

[noisydart]

I have an early B body 8 3/4 in my 69 Dart.  I don't know if it was quite as
long as yours (do you know what it came out of?)  I relocated the perches.
Did not cut anything.  I used a 15x7 rim with a 5.5 backspace which was perfect.
I rtun 2.35-60-15's in a stock wheelwell.  They are perfectly centered.
This combo allows you to run late Mustang 17" rims because the backspacing is the
same. If you go to www.moparts.com and do a search under posts by Clair Davis,
you will see posts related to this.  He runs a B body rear in a Valiant.

[Chris_Holliday]

I swapped a dana 60 from an early roadrunner and only moved the perches.  I used 7" backspace wheels and fit 10" slicks in a 72 swinger wheel well.

[Lars]

I have an early B that I had put in my 70 at one point. I later switched to an A body width rear. The B was fine with the correct offset wheels though.

[Gospel Runner]

When moving the perches what did you use to cut the old perches off? Where can I get a good kit to relocate the springs 2"-3"?

[19swinger70]

you can buy perches from several places. i got a set from mancini. if you are careful, you can cut them off of the b body rear you are using, but i think it's easier to get a set. it just depends on you.

[noisydart]

When I did mine, I ordered a set of perches from PAW., but
they were backordered.  I took the old perches off with a grinder
and chisel.  They were good enuff to reuse which I did, since I
couldn't get the new ones in time.

[Lars]

A welder did mine for me (years ago), don't know how he got them off, but he was able to reuse them.

[Josh]

here is the chart with the dimensions.

http://www.bigblockdart.com/techpages/diffchart.shtml

[demon340v]

the B body rear is nto 3" longer if ur using teh right B body rear.

In my 71 Demon i have a 8 3/4 from a 69 Runner( will miss my ol oem 8 3/4 to my demon)  it had no spring perches so i ordered a set from summit racing was like 14 bucks or something +shipping

with the B body rear i have more space on the back side of the rim going towards the springs.

Overall the B body rear is if ic an remember correctly 1" longer .50 on each side i'm running the stock 14"rally's which i think are a 4.5bs right? and i have 235/60R14's for teh mean time i plan on stepping it up to a 255/60/15 15X8 4bs to get the tire tucked just a bit better with the 15's

[Gospel Runner]

I just want to take a moment to say thank you. It is not everyday that you can find someone who will jump to help you like you gentleman and ladies have helped me. Let me know if I can ever retuen the favor. I will let you know how this project turns out!!!
Sincerely, Gospel Runner

[mrhotrod]

you can fit a 10-inch wheel under your car, I have them under mine with the B-body rearend. they have a 7 1/2 inch back spacing and I did do the mini tubbing just like in the tech articles and moved springs in.