Hot Rods pan hard bar with leaf springs?

Myself and my chassis builder deemed the old standby panhard bar plenty adequate for a coilover car.
I did need a trunk riser for clearance due to the design and ride height.
He did suggest adding an anti sway bar if I had issues, I chose to be proactive instead of reactive.

 

Also note...the "half length" bars (as attached to the center section of the differential) are to be avoided unless you limit the up and down travel to a small minimum.
A "properly" designed bar will be as long as mechanically possible (the outside of one frame rail to the backing plate on the opposite on the axle.
And as noted by others, the bar should be parallel to the ground with the "normal" compliment of driver and passengers on board.

If you just putt around and don't really "drive" your car, the partial or half length bars are ok. But if you actually get out and "drive" it, a full sized bar is a very good thing.
This keeps the body from wandering around the axle while in any type of bend or corner in the road.

This is why a Wishbone or Watts link is a MUCH better option. Side to side movement is almost none.
A diagonal link on leaf springs would be a pain to do. Plus I've heard (more than a few times) of the ends breaking when used on street cars because of the loads put on it. Diagonals are good on drag race cars.

Mike

 

I wouldn't use a panhard bar or a track locator on a parallel leaf spring set up. I would cut and re-weld the spring pads to center up the axle in the car. 1" difference side to side is more than I would accept.

Or, do like 29moonshine said, use a wheel spacer.

BTW, every type of suspension binds with movement at some point in its travel. It's our job to try to engineer it to get the best travel with the least bind for our application. The parallel leaf is probably the most forgiving. My 2 bucks...

 

I had that rubbing problem on a parallel spring car years ago. I put on a sway bar to control body roll and that cured the problem. The car handled a lot better as well.

 

Z shape rear shackle's both pointing the same direction.

 

I don't think I would want to use a panhard bar to shift a rear axle towards one side. That action would put a lot of stress on both ends of the bar, and on the mounting brackets on both ends. You are just asking for trouble.
I would probably recenter the spring perches on the axle so it sat in the car the way it needs to sit, or I would add a wheel spacer to the rub side. The spacer would be much easier, centering the axle perches would be the correct fix, and adding a panhard bar pushing a rear end towards one side would be a whole new can of worms. Gene

 

Yeah. That is a lot off center. Don't see how the car can be square chassis/ driveline wise. Something has to be off somewhere. I think it needs one of my 6 plumb bob alignment jobs to get that thing squared up before adding a panhard bar. (I don't trust the kids with the lasers.)

 

I've had many cars with parallel leafs and never had a panhard bar. All 3 race cars we now have are leaf sring and none have one including our 1/2 mile dirt Super Stock. It's 3000 pound minimum and has a shackle on one side and a slider on the other.
I use a single traction bar on my LSR roadster (avatar) for wrap up with much success.

 

There is a lot more force than people realize on a panhard bar in a corner. I have seen the frame mounts ripped right out on race cars.

 

Back in my day, we raced stock bodied cars. Several of our leaf spring cars had panhard bars, and I had to repair more then a few because they ripped the body end of the mount apart. It was quite concerning when you pushed a panhard bar through a unibody frame rail. There is a lot of force there.
That is why I suggest he not use a panhard bar to shift a rear end for tire clearance. Gene

 

Front Panhard and rear Watts Link; both ends dual elliptical springs..Sorry rear pic not clear..

 

That would work if the tire was rubbing on the inside but that's not the problem. HRP

 

Can you roll the fender lip a bit on the scrubbing side? A baseball bat between tire and fender will give you a bit of clearance and you won’t be able to tell it outside.

 

On road race cars where the stock leaf springs are required by rules, they use a panhard or watts link for lateral location. What they do is float the leaf springs by having wider hangers and shackles than the leaf [1/4" max is needed]
This is usually needed if the spring lacks arch [flat leaf springs]
another trick is to use spherical bearings [similar to heim joints] instead of bushings. This allows rotation of the springs during body roll ,and the springs remain perpendicular to the axle/spring pad.

Don't over think panhard bars or watts links on a road car. A 48" panhard only arcs 0.040" for the first 2" of travel. [less if mounted as I suggested in the earlier posting here]
Most of the instability felt I the rear suspension is Axle steering [or roll steer] cause by wheelbase variations during suspension travel [a Watts-Link won't remedy this]

If all you want to do is move the axle over. Slot the holes [east/west] in the spring pads where the centrebolt goes and test fit.

 

A triangulated link turns one side into a trailing arm . The roll centre is shifted to the side the 2 arms meet at the axle.
The vehicle will have different handling characteristics turning L or R.

This is best left in drag cars

 

Very cool Billy. I didn't realize you had gone with that suspension system, very nice!

 

Adjustable panhard bar, and leaf springs.

I have this on the back of my Falcon, it not only does not bind, it works very well, and keeps my tires from hitting the wheel houses.

 

Yes, quarter elliptic springs on the rear. transverse semi elliptic on the front. My avatar car is a 1932 Austin 7, the UK model that the American Austin was based on, I believe that the later Bantam had semi elliptics on the rear.

As the Panhard bars are quite long on my car, and are parallel to the axle when the car is loaded, any sideways movement of the axles with suspension travel hasn't been noticeable on the road (or race circuit in the past)

 

Indeed, I see you've retained the original Austin Active Anti-Corrosion System

 

I put one on one of my cars!
I took it off? It did work but made the suspension very stiff!
depends on what your looking for?

 

Gimpy, that is a masterpiece! (in over engineering)

 

This is what I want to do. HRP

 

Is there a centering hole on the leaf spring pad welded to the rear housing ? Usually the leaf springs are held together with a bolt that protrudes through the top of the main spring. If so that's what's keeping you from moving it side to side with the U-bolts loosened. Just a thought, but if that's the case, hog out the holes on both pads a bit the way you want to shift the rear housing over and move it over. I wouldn't get crazy on the amount you hog out, maybe one hole width over would be enough and drill a hole next to the existing one ?

 

I have never seen this done before quite like this. It's a great big Jacob's Ladder -- a large version of the small ladder used on current sprint cars. Nice job.

 

I think if you use it to shove the axle over your going to have the frame side of the mount getting ripped off often.

If you read the threads about pan hard bars - stock on 1940’s ford front and back- you’ll see if they are under tension/load during normal ride height your probably going to brake something as soon as you lay into it.

Could you just re drill the holes in the axle pads to move it over a bit?

Seems hokey but it won’t brake and it’s easier than re welding it all

 

HRP,
I'm sorry. I guess I'm feeling grumpy this morning, but please FORGET ABOUT SWAY BARS, PANHARD BARS, PARALLEL SPRINGS AND WHATEVER ELSE. SOMETHING IN THAT CAR IS OUT OF SQUARE. CHECK THE REAR END FOR CENTERED AND SQUARE IN THE CHASSIS. If this needs corrected then you can start drilling holes or figuring remedies to square. If you do this the tire may clear the fender. If it still rubs, THEN a sway bay or panhard bar may help. That rear end is either skewed or shifted sideways. I see premature wear on several different components. Possible vibrations. Car crabbing down the road. Lots of things.
Sorry about hollering, but if you are going to fix something go to the root of the problem before you start fixing. Start at the foundation.
Of course, if the fenders on the car have been crashed and not repaired to the original contours then that could be the problem and I could be full of shit. I would still start with checking the rear end for centered and square. A complete alignment wouldn't hurt anything.

 

Thanks, but just bought it, and trimmed it to fit.

Sometimes its faster to use ready-made.

 

I have a lot of non car related priority's on my plate right now but hopefully I will get a few hours in on the coupe this weekend and make a definite plan. HRP

 

On old Fords with transverse leaf spring suspension it was easy to lower the car by installing long shackles. But if you do that you should install a Panhard rod to locate the axle. Some of the last such Fords in the forties came stock with a Panhard rod on the front axle.

 

Just one more thing I'd check. Is the body centered over the frame side to side? Maybe it's not the rear end/frame centering that's off.