Adjustable strut rods alignment question 74 Dart

[Phreakish]

I didn't have the sway bar disconnected when I set the ride height, but I can see how that would cause me to adjust one side differently than the other. I raised it up and messed with it along with straightening the steering wheel and it was much better. I'm hopefull that with the adjustable strut rods, setting the height with your advice, and another (3rd) alignment, I'll have it riding better. I also ordered new 1.03 torsion bars, just to eliminate that variable, as I got mine used and suspected them of being different from side to side (which may just be the sway bar deal that you mentioned). In the mean time, I had had the wrong (too small) bolts in the leaf mounts. I fixed that and replaced the shackle bushings with urethane. I have a rear sway that is yet to be installed. This thing should ride pretty tight if I can solve the riddle.

Should be easy to measure the bars or check for part numbers to see if they're matched.
If you search around, you can find the proper measurements for setting factory ride height. You can change from there, but it's a good starting point. It requires measuring the difference between the ball joint and pivot point heights, which is a good way to do it and doesn't get skewed by tire height.

Also remember that any time the car is lowered, you need to drive forward/backward a bit to settle the suspension. Due to the way the front end swings, and the built-in bind of the system, it takes a bit of rolling for everything to seek a repeatable position. This is one of the ways that some shops screw up - they change the ride height on the rack, and then start tweaking things without rolling it out. From there, the errors compound and you get a screwed up result. Happened to a buddy of mine with his E body too. I finally found a guy in my town who knows what he's doing, and is earning all my alignment biz from now on!

 

[Ceedawg]

Got mine finished, no bind thru full travel

 

[Ceedawg]

I hope one notices the heim is dead center with the lca bolt so the whole shebang travels in one arc.

 

[72bluNblu]

I hope one notices the heim is dead center with the lca bolt so the whole shebang travels in one arc.

The end of the LCA travels in an arc around the LCA pivot. The end of the strut rod travels in an arc around the bolt in the center of that heim. The LCA pivot and that strut rod bolt are not parallel to each other. The LCA and strut rod are not the same length (which sets the radius of their arcs). You really think that the end of the strut rod and the end of the LCA will trace out the same arc in that configuration?

You changed the radius of the arc that the strut rod traces out by lengthening the strut rod, but, those two arcs are still at an angle to one another and have a different radius. The strut rod and LCA intersect at an angle, you can not make those two things travel in a non-diverging arc with non-parallel pivots. You can change the radius, but, those arcs are still separate and diverging.

If you want them to travel in the same arc you would need to move the strut rod pivot so that it is both in line AND parallel with the LCA pivot. Which would basically just make the combination a wishbone style LCA, much like the UCA is.

And frankly, I've never had any trouble getting the LCA on one of these cars to travel without binding within the range of available suspension travel, even with the shorter off the shelf adjustable strut rods.

 

[Ceedawg]

View attachment 1715804400

The end of the LCA travels in an arc around the LCA pivot. The end of the strut rod travels in an arc around the bolt in the center of that heim. The LCA pivot and that strut rod bolt are not parallel to each other. The LCA and strut rod are not the same length (which sets the radius of their arcs). You really think that the end of the strut rod and the end of the LCA will trace out the same arc in that configuration?

You changed the radius of the arc that the strut rod traces out by lengthening the strut rod, but, those two arcs are still at an angle to one another and have a different radius. The strut rod and LCA intersect at an angle, you can not make those two things travel in a non-diverging arc with non-parallel pivots. You can change the radius, but, those arcs are still separate and diverging.

If you want them to travel in the same arc you would need to move the strut rod pivot so that it is both in line AND parallel with the LCA pivot. Which would basically just make the combination a wishbone style LCA, much like the UCA is.

And frankly, I've never had any trouble getting the LCA on one of these cars to travel without binding within the range of available suspension travel, even with the shorter off the shelf adjustable strut rods.

Well you certainly can’t see to well. You don’t know how a heim joint works? The blue line means nothing for that joint, it’s a BALL. The ball is centered on the pin. There is NO forward and back movement on the lower control arm moving up and down.