Thread: Triagulated 4 link set up

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unless it is strictly for drag racing , some angle on the lowers is an improvement----look under a Mustang up to 2004-----------

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Photos attached the front of the link is about 2 3/4" higher than the back of the link I think I am going to raise the rear by make new holes in the lower bracket???

If it were mine, I'd leave it alone until I could put a few hundred pounds over the rear axle to represent the bed. This'll give you a better idea of what it looks like at normal ride height.

The thing in those pics that jumped out at me was the pinion angle looks terrible! I would try to get it closer before doing the final welding. Then you can use the threaded sections to fine tune it.

Hard to tell from the pics, but Mike is right in commenting on the pinion angle. Should be a whole lot more down! I don't like that much up angle on the lower bars, if you have room to lower the bottom of the coilovers that would help a bit, but a shorter coilover or a taller upper mount (if body room allows it) would certainly help!

What if you made a new front lower trailing arm bracket that put the front mounting point inside the frame rail instead of under it. A well made bracket using 1/4" plate with gussets or boxed in should work just fine. You could then maybe move the rear trailing arm bracket out a bit more to line everything up.

Your set up isn't at ride height so none of these comments are relative-----you need to make up a pair of tubes the length the shock will be at ride height and work with that----------- and generally those kits are set up to be put on the axle housing with the rear face of the shock mount at the same angle as the face of the housing where the punkin bolts in---------

As for the angle with the frame----put the mounts at a width as wide as you can with the inward leaning of the coilover at a reasonable angle and still as wide as you can---the angle with the frame of the lower link doesn't mean much as long as its reasonable with regards to triangulation of the axle tube and the upper link----

What does concern me from your pics is the upper cross bar for the coil over mounting---it carries the total REAR weight of the vehicle and looks like the twist it will get from the load plus the bending from the weight might cause a failure-------

I Hear you on the pinion angle I know that its way off. I figured once i get the links correct I will get the pinion angle fixed. If I mount the front of the links to the inside of the frame the bars will be at even more of an angle. I think raising the rear of the bars higher into the bracket by punching a new hole in the bracket will get them within about an inch of being parallel to the ground. I added marked up the photo below with two white dots the represent the "new holes" so I can raise the lower bars?????
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You do not want to re-locate the rear or set the pinion angle until you are at ride height like Jerry said. What I meant by moving the front location is only to make the lower bars parallel to the length of the frame. Not to change the height of the front bar.

You have the tires on it. So now put the bed on it and set the ride height (or put the same weight on the frame that the bed weighs). I have always had my trailing arms set at a bit of a down angle because the rear of the vehicle will squat on accerlation. Personal prefferance.

I agree with Jerry on the rear shock crossmember. IMO, that square tube isn't nearly strong enough. One solution is a heavy-wall tube with some bushings welded through.

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Jack

Excellent photo showing nice (and desired) wide as possible mounting of coil overs, which also since they are close to the wheel, makes the spring rate applyed more in line with actual rate of spring-

Also, that system of arms on the rear end has virtually zero binding, compared to varying percentages for the triangulated 4 bars systems-------------

And to go a little bit further----------this rear suspension system is not one designed for the ultimate forward traction biting race set up--its for simplicity and a nice ride that can be achieved from proper choice of shock valving and spring rates on coil overs which is easy to fab and mount and makes the ride much more pleasant so the vehicles get used as compared to some cobbled up junk yard rear end assys-------------

Originally Posted by Henry Rifle

I agree with Jerry on the rear shock crossmember. IMO, that square tube isn't nearly strong enough. One solution is a heavy-wall tube with some bushings welded through.

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Jack I thought the same thinking I am going to replace the shock mount with a 2"x2" 1/8 wall box tubing nice catch..... thanks for the picture.