C Body/B Body Rear Swap

[Bruzilla]

Got a question for the interchange gurus out there. How hard would it be to replace an 8.25 rear with drum brakes in a 1974 Road Runner with a Dana 60 rear with disc brakes from a 1974 Imperial?

Also, if both the Road Runner and the Imperial have 440s, would the driveshaft be a direct swap also?

 

[67 coronet]

i didnt know they mated 8.25's with 440's.thought the were small block only.

 

[Bruzilla]

They didn't. My Road Runner was originally a 318 car but I'm putting a 440 in it.

 

[moparmarks]

Its my understanding that it is next to impossible it find parts for the Imperial rear disc, even pads.
Could probably use the Imperial drive shaft but would need to shorten it abit I'd think.
The Imperial rear is 1.75" wider than the 71/4B

 

[Bruzilla]

Looks like Autozone carrys parts for them.

 

[YY1]

You got a lotta wheel well.

That 7/8" per side might not be noticed.

How about the perches?

I'm pretty sure an Imperial has a longer wheelbase than a B body.

Where the heck did you find one of those?

Are you sure they can actually get the parts, or they just list them in the book?
They may have one set of pads on the shelf, and those are the last in the US

 

[Bruzilla]

I was thinking the same thing about the 7/8", but what about actually bolting everything in? With my luck, the holes would be like 1/8th inch off.

Ah... the plot thickens. I just talked to the Imperial's owner, and he told me he thought the car had anti-lock brakes on it. I thought he was wrong, but it turns out Chrysler was the big innovator on ABS and started putting them on the Imperials starting in 1971. So I'm guessing this is where the talk of parts being hard to find comes from. Pads and common stuff you can get, but the ABS parts are likely all gone. So I'm guessing this would be one of those "if you're going to use this, you'll also need to change this, this, this, and this really expensive thing over here."

 

[YY1]

Don't forget the iso-comp stuff...

I wonder how that (mechanical, I'm assuming) ABS works?

I imagine you could defeat the ABS if it came to that.

 

[67 coronet]

i know the lincoln abs of the same years was a vacuum booster like devise that pulsated the brake fluid.i figure the chrysler was prob along the same lines.abs unit was up front and didnt change anything at the wheels at all.is there a diff pad listed for the abs brakes?if not i would think there is no diff in the axle assembly.

 

[moparmarks]

You might want to actually call and check on availibility on the parts. They show the loaded calipers but special order. They don't show a rear rotor.

 

[Bruzilla]

i know the lincoln abs of the same years was a vacuum booster like devise that pulsated the brake fluid.i figure the chrysler was prob along the same lines.abs unit was up front and didnt change anything at the wheels at all.is there a diff pad listed for the abs brakes?if not i would think there is no diff in the axle assembly.

All the owner knew was it's a three-channel system... whatever that means in ABS terms.

 

[emore]

Check that Imperial a little closer, Chrysler wouldn't have put a Dana60 in one ,especially a 74. That 3rd member is most likely a 9-1/4"

 

[Bruzilla]

I went out and looked at the rear, and it is a Dana. The stock rear was the 9.25, but this was one of 1,700 cars that was ordered with the heavy duty towing package.

I also found out the car does not have an ABS package. Apparently this was a $300+ option in 1974 and not many folks wanted to buy it.

 

[68GTX4SPEED]

Does these have the provision for the pinion snubber?

 

[Bruzilla]

Didn't check but I'll look next weekend. Hopefully also get some pics of it. Seriously... you guys would not believe how rusted out the body on this Imperial is. I've heard how the Imperial bodies had a seven-step prep & paint process, but this car looks like it missed six of those steps.

 

[rsd859]

They didn't. My Road Runner was originally a 318 car but I'm putting a 440 in it.

So is mine, I will be watchin this one!

 

[73runner]

Interesting discussion.

 

[Bruzilla]

I'm hoping it becomes a real boring discussion, like "Yeah, all I had to do was relocate a few holes and everything went in fine with no problems."

 

[rsd859]

I'm hoping it becomes a real boring discussion, like "Yeah, all I had to do was relocate a few holes and everything went in fine with no problems."

Ok, let us know how that works out for you!

 

[67 coronet]

wouldnt this really just be measuring the spring perch width compared to your ride?if it matches and the design is the same it should bolt up.brake lines are all about fabbing anyhow.there is only two ujoint sizes on these cars,so at worst you could run an adapter joint.