Hello everyone, I did a search ,but having some troubles confirming my set up. I am putting a c10 truck arm setup in my 53 bel air. I have progressed a bit , but now I’m trying to mount the Panhard. I have it mocked up to about 33” in length and planning to mount it to the axle on the passenger side . The truck arms extend a few inches out behind the axle which I’m concerned will hit the Panhard mount on the frame. I have it set up to be parallel with the ground at ride height. My question is can I run it at a bit of an angle to the frame rail. So when viewing the Panhard from above it would not be parallel with the axle ,but it would be off by less than 5 degrees. Thanks for any info and have a happy 4th.
Is there a reason you cant extend the axle end mount just a touch and make the frame mount match and stay parallel? -rick
I was thinking of that, but it gets awfully close to the gas tank. I am going to have to reinstall the tank and check for clearance. That’s probably the better route.
You can make your mounts higher, lower, and forward or back. As long as you try to keep it level or close to it. You can also make the axle mount offset towards the other side so the panhard bar is a bit shorter to avoid the arm that sticks out to the rear.
Ideally, you want your panhard as long as possible and to be parallel with the axle in both up/down and forward/back at ride height. But, the world isn't always perfect and sometimes compromises must be made. 5 degrees isn't likely to hurt much or be noticeable, unless you're building a road racer.
You will want the bar's pivots to be parallel to each other and parallel to the roll axis. Between them the bar can be angled. If you're using spherical joints you'll have more tolerance for misalignment than with polyurethane bushings.
From a top view ,you can run a Panhard bar at a diagonal [angle] and you can bend it around objects ["J" bar] The Panhard is an imaginary straight line between 2 pivot points. Drag racers use a diagonal bar on 4 link set up which is effectively a diagonal Panhard bar [viewed from behind] From a horizontal view from behind, the Panhard bar needs the pivots to be equal distance from the centreline of the car. [street ,or road-racing cars] The roll-centre of a Panhard is the halfway point between the pivots [this needs to be central in the car] But don't overthink this too much.[I have shifted a Panhard Sideways to correct bump-steer on cross-steer front ends] You don't want the set up to be parallel with the ground at ride height. It is much better to have the chassis pivot 1" higher than the axle pivot. This reduces the sideways arc in the 1st 2.5" of suspension compression. A Panhard bar will always move through an arc, so the first 1" it arcs outwards, the second 1" [2" total] it arcs inwards back to zero, the third 1/2" [2.5" total] the angle is more accute and arcs inwards On a 42" Panhard bar the numbers are 1" travel [+.010] 2" travel [ 0.00"] 2.5" travel [-.020"] This ^^^ is suspension compression where the tyres are loaded more If the Panhard bar was parallel [horizontal] at ride height , 2.5" suspension compression would arc -0.070" The arc situation is more accentuated during suspension droop but the tyres are unloaded so the effects are not felt. there is 0.085" sideways arc at 2.5" droop One trap with having a diagonal Panhard bar [from top view as being asked] is the LCA's need to be reasonably neutral [LCA's = truck arms] If they are set up with a lot of Anti-squat you get a change in wheel base with suspension compression [WB lengthens] The change in WB also changes the triangulation of the diagonal Panhard bar [fixed length] this causes the axle to shift sideways. This ^^^^ is one of the reasons why Watts links are preferred by racers
Here is what I meant by Roll Centre The RC should be at the blue "X" but it is actually at the red "X" due to the frame pivot not being equal distance from the centre to the axle pivot
Thank you for the very informative explanation. I read it several times and will probably read it a few more to be able to grasp everything.
This is a good video for basic set up. Take notice of the bit at the 2:43 mark. https://www.youtube.com/watch?app=desktop&v=liR1--EHMg8 But my best advice is to set it up as Kerrynzl suggests. If you aren't sure, ask. He is usually happy to help.
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