Rear sway bar on standard rear lower control arms

4SPEED427 · A Poncho Legend!

Rear sway bar on standard rear lower control arms

65sssd · Poncho Master!

You have to weld them in. I just boxed mine.

4SPEED427 · A Poncho Legend!

I want to avoid welding because then I would want/need to replace the bushings right away.

65sssd · Poncho Master!

Drill through both sides of the trailing arm and sleave the bolt inside the valley of the arm. A caliper sleeve would work good. Bolt it right through. Did I lose you?

4SPEED427 · A Poncho Legend!

Nope, still following. That's how I did my car years ago but I think there needs to be more bracing in there than just a couple of sleeves. On a hard corner I can visualize that channel still wanting to bend. I was thinking something that runs most of the length inside that U channel. I just haven't figured out yet how it gets held in place.

I guess if I have to weld I could pull the arms off and keep the ends chilled where the bushings are so the rubber doesn't get overheated.

Alas, I guess I may just have to make up inserts and weld them in. I hoped not to. No hurry anyway, lots of time to think on it, future project.

cdnpont · Canadian Poncho Superstar!

I think just the addition of a rear bar makes such a huge improvement that any further boxing likely won't improve the feel much if any. My theory is it might even be better to have some slight twist to the arms in the hardest corners, that way all the deflection isn't transfered entirely to the bushings. Two bolts with inner spacers should brace the arm through the center more than enough.

I suppose you could drill 2 more holes out towards the bushings, and bolt through the arm with spacers, maybe make some heavy "C" channels that you could insert in the arm. But would drilling more holes just add a place for a crack to develop?

I saved this picture of boxed arms. The person fab'd these spacers to be welded in. I think I've actually seen these parts for sale somewhere. Look to be perfect.

dualquadpete · Canadian Poncho Superstar!

I did a 69 Cutlass awhile back & used some square tubing that "just" fit inside the trail arm. Drilled out the holes & fitted the sway bar, stitch welded the tube to trail arms after it was all fitted together. Owner is happy with job & says the car goes around curves like its on rails!!!!

4SPEED427 · A Poncho Legend!

Now there's a thought. I may look for some tubing. That would do it.

SD 396 · Poncho Master!

You can buy the piece that inserts into the control arm which takes a lot of twist out of the rear arm and allows for the adding of the sway bar. The piece is stitch welded in place with 4 or 5 welds down each side.

CLICK HERE for a procedure on welding it in.

2drpost · Uber Guru

added a rear bar to my bel air, drilled through both ends and used pipe spacers through the center.

seventy2plus2 · Canadian Poncho Superstar!

I have the instruction sheet from the GM manual that I can send you (though it might take a bit to find the sheet). The forward bolt only goes through the inside edge of the control arm, the rear bolt goes through both sides and I used a piece of pipe as a spacer to keep the arm from collapsing.

Spacers are also required between the inside edge of the control arms and the sway bar.

4SPEED427 · A Poncho Legend!

Thanks Clint, I have that assembly manual picture. I have some of those shims between the bar and arm. I have saved those things for 20 years hoping to need them again one day!

General consensus seems to be that those pipe spacers I used years ago are enough. I guess I may just try that again then.

66 Grande guy · Canadian Poncho Superstar!

Hi guys I also have the page from a 66 Chev assembly manual and an original F41 set with all the factory pieces that I'm about to put on my 66 (today as it happens) so i will assemble the pieces according to the manual and takes some pics for reference before I bolt it all up. I don't believe the factory setup called for boxing rather it had spacers for the rearward bolts that tied the two section of the lower arm together but the front ones just bolted on to one side of the lower arm. (with a reinforcing plate against the inner lower arm for both bolts)

For me if it was good enough to last under a 68 396 four speed (which is where we scavenged it from) its good enough for me with my old man driving style

I'll follow up as soon as I can here.

-- Edited by 66 Grande guy on Monday 5th of December 2011 01:24:17 PM

-- Edited by 66 Grande guy on Monday 5th of December 2011 01:25:20 PM

4SPEED427 · A Poncho Legend!

Did you guys see this, he took parts off a 396 4 speed B body? See that??? It's not just me....

66 Grande guy · Canadian Poncho Superstar!

It was one of my brothers to be technical but i did manage to end up with a few pieces so i guess that does make me a scrounger too.

Here is a quick mockup of what I was able to get from the assembly manual with the pieces I had. i was wrong about the reinforcement plate sandwiching the inner part of the lower control arm. From what I can see the assembly would go like the pics below and the sway bar actually is not bolted directly against the lower control arms but stands off a bit with a couple of spacers holding it off.

There is no boxing shown on the manual either.

Here ya go! The top of the pics is to the front of the car. The white cardboard pieces are meant to be the inner and outer sides of the lower control arms.

Does this look correct to you guys?

-- Edited by 66 Grande guy on Monday 5th of December 2011 05:41:55 PM

seventy2plus2 · Canadian Poncho Superstar!

66 Grande guy wrote:
It was one of my brothers to be technical but i did manage to end up with a few pieces so i guess that does make me a scrounger too.

Here is a quick mockup of what I was able to get from the assembly manual with the pieces I had. i was wrong about the reinforcement plate sandwiching the inner part of the lower control arm. From what I can see the assembly would go like the pics below and the sway bar actually is not bolted directly against the lower control arms but stands off a bit with a couple of spacers holding it off.
There is no boxing shown on the manual either.

Here ya go! The top of the pics is to the front of the car. The white cardboard pieces are meant to be the inner and outer sides of the lower control arms.
Does this look correct to you guys?

-- Edited by 66 Grande guy on Monday 5th of December 2011 05:41:55 PM

Yup, that's what mine look like.

67Poncho · Uber Guru

Carl Stevenson wrote:
Did you guys see this, he took parts off a 396 4 speed B body? See that??? It's not just me....

Sorry Carl... Didn't see that thread but I do see red when I hear of your wrong-doings!!!! (bahahaha)

And besides, at least he took other parts off of it.... You just performed open heart surgery.......... Like an illegal organ removal!

-- Edited by 67Poncho on Monday 5th of December 2011 06:51:09 PM

67Poncho · Uber Guru

Here is a thread that Mark posted and an excerpt from it.........

http://canadianponcho.activeboard.com/t34858786/got-the-rear-stabilizer-bar-on/

Basically the large flatbar goes on the diff side of the control arm. There is a 1/4" "special spacer" on top of that at both bolts between the plate and bar.
Two small 1/16" flat washers per side at the rear bolt between the bar and the special spacer.
Special spacers on the nut sides of the bolts as well.
A piece of pipe inside the arm at the rearward throughbolt.

You could spend a fair bit of time shimming it to avoid any tension on the arms, and my bushings are tired and the arms were actually moving quite freely side to side, so it all will vary car to car. New bushing and It'll be more critical to keep it neutral.

My Spohn bar needed a 1/16" washer on the front bolts as well. It's actually said to be a Chevelle bar that is the same as Impala...but I wonder. I think it is a little narrower than the F41.

Cheviac · Guru

I used a sway bar off an early to mid seventies fullsize Chev, the inverted u channels pulled out with the bar and slipped right into my 66 Impala arms. After that I've been salvaging every one I see.

67Poncho · Uber Guru

Cheviac wrote:
I used a sway bar off an early to mid seventies fullsize Chev, the inverted u channels pulled out with the bar and slipped right into my 66 Impala arms. After that I've been salvaging every one I see.

Same here Ken.. Even the '77 till end of "B" production will fit with a spacer added...... I have a couple of those Police bars on my cars....

Not factory in looks but none of my cars are 100% anyways..... (except your wagon!!!)

-- Edited by 67Poncho on Monday 5th of December 2011 07:05:44 PM

427carl · A Poncho Legend!

Here in South Western Ontario, we do not have any curves in the road

to make a sway bar work

4SPEED427 · A Poncho Legend!

67Poncho wrote:
Here is a thread that Mark posted and an excerpt from it.........
http://canadianponcho.activeboard.com/t34858786/got-the-rear-stabilizer-bar-on/

Basically the large flatbar goes on the diff side of the control arm. There is a 1/4" "special spacer" on top of that at both bolts between the plate and bar.
Two small 1/16" flat washers per side at the rear bolt between the bar and the special spacer.
Special spacers on the nut sides of the bolts as well.
A piece of pipe inside the arm at the rearward throughbolt.

You could spend a fair bit of time shimming it to avoid any tension on the arms, and my bushings are tired and the arms were actually moving quite freely side to side, so it all will vary car to car. New bushing and It'll be more critical to keep it neutral.

My Spohn bar needed a 1/16" washer on the front bolts as well. It's actually said to be a Chevelle bar that is the same as Impala...but I wonder. I think it is a little narrower than the F41.

I wonder why it's not necessary for the other bolt to incorporate both sides of the control arm?

And yes, in the GM parts books, the A body and B body bar is the same part number. The only B body bar I've ever had I let go with the car. It was a 68 427 car that obviously had F41, but I was 20 and didn't know any better....

Otherwise I've installed A body bars on B body cars and it's fine.

Steve C · Guru

I installed a sway bar on mine 15 or so years ago. I just used some round tubing spacers. Works fine.

77srx · Addicted!

Found this site, don't know if it still exists or ? but it looks like a nice sanitary set up.

http://www.nitemareperformance.150m.com/B%20Body%20fullsize%20rear%20anti-sway%20bar%20kit.html

2qwik2c · Poncho Master!

Those types of sway bar kits look absolutely terrible installed on these full size cars, I would find a gm A and B body sway bar. They are out there as they were still available a few years ago from gm.