Replacing strut rod bushing with rod end?

[JustJohn]

Planning out how to fabricate this for a 69 Impala and I am stuck at the adjuster diameter.

5/8" is much easier to get the parts together and assemble (I can't find the right 0.68" or 3/4" shaft clevis bracket) but the factory strut rod is 3/4" so I have some concerns about strength. Probably unfounded as I doubt the factory part is hardened steel but I would be curious to know what other people are using on a joint that has a critical function.

[JustJohn]

So I went ahead and roughed in a design. I'll pull the real part off to get the dimensions down. This just leaves me one piece to machine and a couple of weld beads to lay down.

Thoughts?
112379

[Carl @ Chassisworks]

What you are contemplating is fairly common but it does have some drawbacks. This is similar to how we used to make our Mustang strut rods and how several other companies still do.

1 - Strut Rod Length. Unless you can fabricate a mount that places the pivot for the rod end in the stock location, you have modified the suspension geometry. It may be improved, or it may not. You would need to do the calculations to determine the outcome.

2 - Mounting. The typical clevis mount will tend to rotate in place as time goes by. The drawback to this is that the rod end will start to bind. And once it starts to bind, it will fatigue faster and if neglected it will lead to until eventual failure.

3 - Noise. There's gonna be more of it. Rod ends are designed to transfer energy, not be nice and quiet.

For your car, we now offer a one piece lower arm with an isolated pivot assembly. http://www.cachassisworks.com/p-1187-impala-65-70-gm-full-size-gstreet-coil-over-suspension.aspx
https://static1.pt-content.com/images/pt/2015/05/5706H30-1.jpg

[JustJohn]

Thanks for the reply. I like the Chassisworks kit, just not ready to take it quite that far yet. Trying to drive it through the summer/fall before taking out the frame.

If the pivot you are using is commercially available, I wouldn't mind trying it out in the design. How much travel are you getting out of your kit? Visually, it looks like there isn't a lot of angular movement available.

[Carl @ Chassisworks]

If the pivot you are using is commercially available, I wouldn't mind trying it out in the design. How much travel are you getting out of your kit? Visually, it looks like there isn't a lot of angular movement available.

The pivot joints are not sold separately. I don't know the motion ratio off hand so I can't tell you the total travel. However, there is no bind throughout the entire travel range.

If you're just trying to drive it until winter I would just replace the stock rubber bushings and drive it. Don't use poly bushings in the strut-rod location, poly can cause other issues in that position. That way you're saving some money and effort to be burned when it gets cold.

[JustJohn]

Thanks. I'm guessing +/-10 degrees misalignment on a typical spherical plane bearing.

Planning on laying out the entire frame in CAD when I get there to work on some simple deflection analysis with a goal of making the existing chassis stiffer in rational ways.

One other thing I'm curious about - it looks like you chose to using "softer" polymer bushing in the upper and lower control arm pivots. I have seen some with a spherical bearing lower and "delalum" upper pivots. Is this just an application choice due to the ride preferences for a bigger car or were there other considerations?

[Carl @ Chassisworks]

Partly ride quality and partly the variance from one chassis to the next doesn't like the use of a lower deflection material.