Thread: 4link

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I'm putting a trangled 4 link on my 68 firebird. Can you put the top bars to the rear of the car? Or do you need to cut the bars.

wouldn't be ideal plus you have fuel tank in the way and to triangulate them would take some imgeneous fabrication to the trunk floor


are you using a set up from some chassis company or designing this yourself?


And welcome---seems like participation from Colorado is picking up

Have lots of questions.
1) Purpose? (What do you want from the suspension?)
2) Like Jerry asked: Off the shelf or fabbed?
3) Do you have design experience with this type of suspension?

I don't think you have the experience or you wouldn't be asking this question...
I did a quick mark-up in Paint for you to illustrate the problem with "rear" mounted upper bars in a four link suspension.
4 LINK SKETCH.png
During acceleration the upper bars in the top drawing will pull the rear pinion angle "up". This defeats the whole "control" of the pinion angle purpose of a four link suspension. The suspension should be designed to limit pinion angle change during suspension articulation. The rear mounted bars will cause all kinds of traction and handling issues as the rear end moves and tries to rotate around two different arcs of travel.
This is not the way to build a good suspension...

Another concern is you asking about "cutting" the upper bars. IF this is an off the shelf suspension you do not want to start cutting things up and moving points around. Doing so changes the entire action of the suspension and will do nothing to improve it. Cutting will change the geometry to the point that you need to entirely redesign the system. Don't cut it up unless you know what yuo are doing.
Mark

about the only cars I know that would use a rear upper bar are circle racers and they would use it a floater mount ont the axle tube with a separate forward bar for weiht transfer/drive line u joint angles


Are you going to coil overs????

Thanks for all the info. This is from a company that said it was for a68 firebird. The problem I'm having is mounting the upper bars. No place to mount the front.

Astroracer's given you the right answer, pictures to show it and good advice on not cutting any links. Did your "kit" come with any instructions from the supplier? If not then how are you supposed to know how they designed the members? Attachment points are key to proper operation. I'd be calling them.....

What company?
The 1st gen F-bodies are unibody cars. If this "suspension" is to do it's job it should have been provided with some sort of "structure" to attach the upper bars to. It should tie into the existing frame rails either welding or bolting in. You will probably have to cut the floor to make clearance for the structure and upper bars.

I didn't get any instructions so I will call. Thank you for the help.

1st gen Firebirds and Camaros are leaf spring cars, so we can assume you're switching over to coilovers??? Lots of good ways to hook up a leaf spring car without all the fab work required to switch to coilovers and a 4 link...........