QA1 Six-Link Rear Suspension Conversion Installed

Actually I am a Mechaical Engineer in automotive. And car suspension is tested on jigs on a test stand that replicates the vectors of motion that particular car suspension goes through. We change the loads applied and angles the force is applied. We also test each part over and over individually to break them. And they are tested in rooms that replicate temperature and conditions (salt spray). I know, I've been designing the test equipment for years. But our Heim joints (albeit way bigger) are larger for increased loading. (We actually can see 1/4" up/down or side to side movement in the upper ball joint location on cast iron steering knuckles during testing).

I can tell you that a Hiem joint will always have a premature life if it's "swivel" is out more than 5 degrees total. Best not to have them swivel at all on the ball, We blow through them if there is a problem with a fixture design and the load we apply changes the vector more than that. When we correct the fixture design misalignment, the Hiem's durability drastically goes up. And with parts changing all the time from R&D changes to increase strength and the constant drive to use the least amount of material to make a part, loads are going everywhere. A part aligned on one fixture, becomes misaligned when it is revised with changes.

No, I wouldn't want Heim joints everywhere because of the harshness (they aren't an insulator) and the damage they can cause where they mount is the biggest negative. And you can't really run a Heim joint if it is swiveling more than 2.5 degrees off the shaft its mounted to when you apply heavy loads. No, it's not 11 degrees or what ever the manufacturer says it can swivel. Machine/fixture designers know this. Actually poly/rubber bushings and adjustable links seems to be the best for cars driven on the street.

With that said, look at how BMW eliminated A-arms in the front of some of their cars. Everyone said that was junk, over engineered, all those links will bind at GM. Then a year later GM was copying it in their G8 prototypes. It proved better for handling.

All of that doesn't mean we shouldn't look at the investment QA1 made in this system and see how it actually performs with an eye to being positive. There are draw backs to all suspension. Torque arms can have squat and brake hop problems, 4- link's can bind with lateral loads, 3-link can eat up space where the 3rd link to properly adjust pinion angles, leaf springs can twist in weird shapes and change pinion angles and can bind. It's all blah blah blah... Because someone might just find a way to make something work in any of them.

Where's the guy that said at SEMA this out performed a new Challenger/Charger?