Projects What do you guys think of this wishbone/ladder bar connection?

I've built and adjusted ladder bars (32-36") for Drag racing...it's a pain no doubt.
Using adjuster units like this setup is using makes it easier.
The sheer length of the bars related to P&J style ladder bars would make adjustments somewhat easier due to the shallower angle between the connected parts at the rear of the ladder bar...especially when you consider the web is usually about half way up the length thus allowing some minor flex.

In a street driven Hot Rod, I just don't see the need for this constant adjustment anyway, certainly not to the point that the bolt threads actually wear out!
If a builder missed the mark that bad in construction...well, it isn't the limited adjustment they should be pissed at.
It's their own inability to use a measuring tape that should have them banging their head! LoL

I mean...36 radius arms have no adjustment at all at the rear and its not particularly hard to mount them. You just set them properly during the build.
Torque arms are the same deal.
As for pinion adjustment...set it and forget it during the build.
This whole joint is a complicated means to a simple end.

As for bushing wear if they were used...the correct bushings would need to be larger than say common 4 bar style bushings and made of rubber. Like Chevy used in the truck 2 links.
Using improper parts will certainly cause premature wear.

However, use the correct rubber bushings and it wouldn't be surprising to see them last the life of the car.
I'm doubtful the same can be said for the joint we're discussing, what with sideways loaded Heims and no greasability or even grease seals for that matter.

Nope...I'm totally unconvinced that this mousetrap is better than the old one.

 

I'm not seeing this as a good setup myself. I understand the single pivot in the cross member, it would eliminate the inherit binding all styles of ladder bars when only one side goes up on a bump. I've seen similar setups on rock crawlers where articulation is real important.
I don't like the way the Hiems are mounted, every time the suspension travels they move in a direction they weren't designed for. I imagine they allow for enough movement but I see premature wear. I think they should be mounted vertical so they pivot like a bearing.
The adjusters on the upper bars being on the front seems odd. Race style bars have those type of adjusters (on the back lower) but they are not for setting pinon angle (that should be done on setup), they are to adjust chassis preload, not really a concern on a street car. I assume since they are on the front the upper and lower bars do not tie together with a gusset or tie bars, something I'd want, particularly if they are over 2' long, but admittedly .125 wall cm probably won't flex much.
My thoughts are they designed this setup to look "trick" and that does sell products, I just don't see good engineering behind it.

 

Not sure. My little monster is only pushing around 290HP through one of those setups. Nothing has broken yet. But I keep tryin.

 

I'd like to see more detail of that main pin as it enters the crossmember.
It looks to me like all the axle forces that push the car down the road are passed into the top and bottom plates which look to be just plug welded to the 1-1/4 inch "beefy" 4130 main pin. There is just a small hint of discoloration at the front of the plate, suggesting the plate is at best tack welded to whatever shoulder or thrust collar is on the main pin.
If one wheel is on something slippery then one wishbone will get most of the 1000 lb plus drive, and the plates will try to torque the plug welds.

Going over bumps while braking will tug the main pin backward while also rotating, possibly trying real hard to unscrew that bolt

 

Im only a young hack and my opinion is based on my own experience but my take on it is this. The failures I've seen on rear end setups are generally at the axle housing not where whatever is being used to locate the rearend(bones, ladder bars) ate attached. I like the adjustability of the top arm, I think controlling the pinion angle for different conditions(track day etc) is extremely beneficial. I think the amount of joints and adjustment at that end of the setup is a benefits a wouldnt consider them more points of failure.

 

This works.

 

Thanks for the input guys !