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FMJ-body rear sway bar on 68-70 b-body?

ChargerST

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Does a factory rear sway bar from a mid 80s Diplomat fit on a 68-70 b-body? Width is apparently 44"
Has anyone done that already?
 
I have one on my red car.

IMG_1693.jpeg


It mounts to the body in a self explanatory way but You’re on your own on how to arrange the connection of the end links to the axle. I modified a strut to work. I’ll dig around and post a few pictures when I find them.
The short story is that yeah, they fit. They hug the forward part of the axle hump. Exhaust clears fine.
Mine came from an Imperial, I have referred to it as an ‘83 model but without looking at my notes, I’m not 100% sure. It is 3/4” in diameter.
 
Thanks a lot! I have a Diplomat bar coming my way and it seems that the ends are shorter than on a B/E-body bar (looking at pictures on firmfeel website) - could be wrong though.
I was planning on fabbing a mount similar to what firmfeel sells but that won't work if the ends are indeed shorter (the links between the axle and the sway bar are located behind the axle).

Edit: found this - looks like it should work

Adding rear sway bar pros or cons

Many years ago, I took the complete rear sway bar setup out of a junkyard '80's Police Diplomat and installed it in my '67 Coronet station wagon. I had to modify the frame brackets because the B-body frame rail is wider than a Dippy rail. This made a huge difference in how the wagon handled. I had no clearance problems with this addition.
A few years later, I decided to put a rear sway bar on my '67 R/T to solve a problem of my rear tires getting scuffed. The tires had clearance around them as the car sat still, but in actual driving, the car moved around on its suspension enough that the tires were getting marked. Since junkyard Police Dippy's were now scarce, I ordered a rear bar from Firm Feel. When it arrived, I was surprised to see that it looked identical to the Police bar I used years before on my wagon.
 
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My mounts are a bit crude looking but they work and have not broken in 10 years. The flat/straight part of the bar where it attaches to the frame rails is close enough between the different cars to still fit just fine.

6 2020 H.JPG


I welded a bracket to the axle housing instead of using the add on plate like the Firm Feel bars.

52.JPG


The gold colored D mount bracket is aftermarket. The natural finish brackets are OEM Chrysler.

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It clears the differential just fine. Eventually, I want to redo the end links.

Rsb end link L.jpg


These are crude and sloppy but they work. I think I'll modify these:

Link 3.JPG


I could cut the loop off of the one on the right and weld it to the bottom of the one on the left. I'd then have a loop on the bottom and a swivel on the top, no bushing.
 
These pictures are great and I like how you did the axle bracket - looks factory to me!
As for the end links, have you thought about using heim joints for the axle attachments? Or would this transmit too much noise/vibration to the body?

Anyways your post will effectively raise the demand for FMJ rear sway bars!
 
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I've posted about it before. The cars have really thinned out over here on the West Coast. I'd grab them at the junkyards if I saw them but THIS one is the last one that I saw and it has been about 10 years.
Heim joints? No way, man. I don't like them for street cars. They cannot retain grease and don't do well long term.
The links that I posted are ball jointed with Zerk fittings to grease them. I have them on the front sway bar and they make no noise. The simplest is the standard strut links with bushings whether they are rubber or urethane but with those, the bushings wear, deflect and shrink leading to free play. These ball jointed links are a huge step UP !
 
I did that installation on a 1967 Coronet station wagon about 30 years ago. The frame attachment brackets for FMJ are too narrow for a B-body, so I had to purchase a second set to cut, section, and weld to make wide enough for my rails. The spring/link bracket came from an E-body. Years later, I bought an aftermarket rear sway bar kit from Firm Feel to install on my 1967 R/T. It included that identical FMJ bar, and the appropriate frame and spring brackets. The nice thing about this setup, is that it is hung from the frame, not adding much weight to the suspension.
 
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Does a factory rear sway bar from a mid 80s Diplomat fit on a 68-70 b-body? Width is apparently 44"
Has anyone done that already?

I remember when I bought this “Imperial” sway bar. I put Imperial in quotation marks because I don't consider the last of the Imperials to be worthy of the name.
I had previously put a Diplomat sway bar in a 73 Duster around 1996 and I had figured that it might also fit the Charger. In a stroke of luck, it fits as if it were made for the car. I had an Addco 7/8” axle mounted bar and didn’t like it. The car was twitchy and wanted to hang the tail end out on rapid turns. The 7/8” size was too much. I pulled the Addco bar and drove the car around a bit and felt that while it did handle well, it still had some body roll that I didn’t like.
The FMJ rear bar is just shy of 3/4” and the lever arms are slightly longer which lessens the rate a bit due to leverage.
This one slipped right in….

IMG_2072.jpeg


Note how the half loop moves with the axle to clear the differential.

IMG_2073.jpeg


The mounts fit great.
IMG_2074.jpeg


This never hits the body.

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You can see how it steps in from the frame rails.

IMG_2077.jpeg


IMG_2078.jpeg

Again, the end link is where I still need improvement.

IMG_2075.jpeg


The car is up on the lift at the moment so the axle is at full droop here.
Cheers.
 
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Thanks again! These pictures are great! I only need to figure out the axle mount as I want to use the same ball joint end links you posted above - in order to do so the sway bar eye should be level to the the axle. Have to check but maybe I have to move the axle mount closer to the axle itself or even on top and use really short links.
 
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