panhard vs track bar - need to understand better to fix prob

[Boones]

Still working to make the my 53 chevy wagon a better driver. It likes to wiggles running down the road.

Background:
I am running a 81 Malibu rearend and factory 4 bar set up. In place of coils I am using airbags. The rear is square to the car and it does not crap down the road. I am running radial tires also. I recently added a factory Malibu sway bar and it did reduce the wiggle alot. The factory sway bar mounts to the lower 2 bars (runs along the lower bar and is attached with two bolts and then hangs below the axle and pumpkin and does not touch the rear) almost tying the links together.. Before adding the sway bar it could be dangerous at times with the rear end moving side to side over an 1". Do to limited space my shocks are only angled about 10 degrees as putting them at a 30 degree angle was not possible. (actually dented a shock from the wiggle causing it to hit the frame rail)..

Possible Solution:
I am now to the point where I would like to add either a panhard or trackbar to remove the little wiggle that still remains.

Panhard Bar:
My problem is there is no room above the rearend (4 bar mounts and airbags are above) and there is no room behind because of the gas tank (factory tank contours around the rear) A panhard would have to be mounted low off the bottom of the rear and to the frame (Not sure what problems this would cause)

Trackbar:
I was thinking of mounting a diagonial bar (trackbar?) between the lower front 4 bar to the opposite side rear lower bar to tie the bars together since I have room in that area. Will this work and what size bar do I need I figure I would use Heim joints to allow movement as it travels up and down..

So what are my options and which would serve me best.
Thanks in advance for your help

[Rocknrod]

Sounds almost like the air bags cant give enough preasure to keep the axle under the car... at least to me anyways!

I'd try running the preasure up and seeing if that cures it... http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

[SKR8PN]

Did you keep the original "angle" on the upper and the lower bars or did you run them a little bit straighter? If you kept the angles correct,it should not wiggle any at all.
Have you checked ALL the bushings in the four bars to insure they are nice and TIGHT!!! Use the correct size bolts in the bushings AND the frame mounts??????? Checked the frame for any weakness's???

[ELpolacko]

If you used the factory Malibu geometry when you installed it I would say the bushings in the upper control arms are shot. We are talking about a GM triangulated four link, correct!?

Airbags are hell on stock rubber bushings, the extreeme changes in ride height tend to rip the old bushings from their vulcanized casings.

Have you noticed any squeaking?

I would suggest replacing the busings with Energy Suspension polyurethane.

[Brock49Ford]

Hey Ken,
I'd try to figure out a way to put a Panhard bar on it. I know easier said than done. I never looked under your wagon when you guys were thrashing to get it done, I was trying to get my car going too. You don't want to run a Diagonal link on a street car, it will cause your 4/Bar even more issues than it would solve. Pretty much for racing in a straight line. Not real street friendly. We have a new weld in high misalignment Panhard bar setup that was designed specifically for cars with a lot of rear end travel. Works really good on air ride cars. Let me know if you need a 2004 catalog. Hope that helps some.

Brock

[Hot Rod To Hell]

Are you sure that the rear is actally moving??? There are several other things that cause a very similar feeling going down the road... With the car jacked up can you move it side to side? If so, and the angles are all correct, I'd replace the control arm bushings, and/or box the control arms. BTW: what are you runnung for tires (front and rear)?

[Boones]

Brock, I will send you a PM with my addy for that catalog.

As for the rear, It has new bushing when we installed the set up and they still look good. I did not mention one piece of info just to see if someone mentioned my concern and you did.

I am not sure if the frame attachment points are of the same dimensional tightness, width (as the factory attachment points) and may have a little more width/play then stock Malibu which may be causing movement. The bolts I think are the same as stock (but new) but I will have to double check.. When the car is on the ground or jacked up it feels tight, it is only now wiggles when hitting a bad roads or I get high winds blowing on the side of it... I would still like to eliminate the feeling as I do not feel comfortable to let the wife drive it incase (plus with super quick steering it enough to pay attention - I am used to it so I can adjust)

can I run the panhard bar below or at the bottom of the pumpking. I thought about building a bracket that would bolt to the rear cover and go over to the frame.

I have thought about relocating the bags to the just behind the rear just below the frame (where the leafs would have been) so I could make a panhard bar above the 4 bar...

[C9]

You can run a panhard bar so that it extends out in front of the carrier a ways by installing a steel bushing and long bolt on the right front of the rear axle.
Similar to what the lower mount of a coilover looks like on many roadsters. They're spaced 1" back and not a problem with the entire weight of the cars rear on them.

I used a coilover lower shock mount - short model - upside down on the 32 and was able to get the 1" tubing* panhard to sit out far enough in front that it didn't hit the carrier on full compression.
The panhard is straight and has no bends.

*1" tubing is overkill, I used it cuz I had some left over from making the rear 4-bars.
7/8" or 3/4" works fine as long as it's .120 wall.

[Boones]

C9, thanks for the suggestion, I will have to look as see if that will work.. It is a tight area due to the back seat in front and the gas tank right behind..

[C9]

Here's another thought - the panhard in the 31 is behind the rear axle.
It's very close to the bulge for the carrier, in fact it misses by 1/8" at full compression of the suspension.
Something like this may work for you and you'd still clear your gas tank.

Keep in mind that if you have 4" of suspension travel and the panhard is mounted so the center of the panhard is on center with whatever would conflict with the rear axle when it bottoms out you don't need 4" of clearance there.
A little over 2" would do it because the center of the panhard only travels 2" if the movable end travels 4".

You do need to leave a little extra clearance due to the rear axle can bottom on one side only and the panhard doesn't rise as much as it would with both sides bottoming out.

The panhard in the 32 is pretty close to a carrier rib, but it's never touched.

There are guys running panhards with a curve in them.
You'd probably need 1" tubing for that and the curve shouldn't be too sharp, but it is a way out of a tight situation.

As for the 1/8" clearance mentioned on the 31, that was measured at full bottom-out and the 4-links are at their rearmost position - due to their arc as they swing.

Note too, the panhard mounting bracket on the right side.
It's made from 1 x 2" x .120 wall rect tubing cut at an angle and gusseted to resist sideways movement.
A crush tube is welded to the top of the rect tubing for the bushing bolt. (The crush tube is 1" cold rolled drilled for a 1/2" bolt.)
Frame mounts are a pair of 3/16" tabs with a 3/16" piece welded partially over the top to brace them from sideways forces. Not that there will be much sideways force, but there will be some and it doesn't hurt to reinforce it a bit.