Still not sure what you want here . Are you asking for the angle of the upper a-arm from the balljoint to the k-member? Where do you want it measured, and at what ride height? I would just set the lower a-arm where it needs to be, and wherever the upper one sits is where it sits.
It's not easy to visualize where the center of the lower balljoint is.Back to the LCA transverse angle, I'm still finding contradictions on this angle. I need some assistance and guidance here so I can move on...
I read that this LCA angle, measured from the pivot point of the lower ball joint to the pivot point of the inner LCA pivot is "0" degrees. This make more sense to me and visually looks very simular to my C4 Vert..
Is that z measurement stuff from GM? If it is, it seems like it should be reliable but it does seem high. Note that it's also for an EARLY C4 since the tires are listed as 255-50VR16. They went to 17" wheels in 88.The "Z"measurement procedure puts the bottom of the front suspension cross member, what seems to be too high !! With my car rack tied up I have no means to check my C4's engine cradle high nor the LCA. It would be a nice reference, but prob not reliable. So, how do I set the correct ride height, exactly.
Also, why would "Z" increase from shipping weight to curb weight? Curb weight is with full tank of gas, and shipping weight is half a tank. Why would they ship with gas? It doesn't make sense that "Z" would increase at curb weight. Notice it DECREASES in the rear and it's essentially the same measurement.
I just measured my frame jig and I get only 19mm for the "Z" measurement if I'm interpreting it correctly. When I put a level on the top of the lower a-arm where it's shown as level in the drawing (just to the right of the pivot), I measure the a-arm being level and I'm pretty sure the steering arms are level there too. I had some measurements for the UCL and LCL pivot points on the other thread, as well as UCL/LCL lengths and spindle heights.
It seems to me that a line between the LCA pivot and the lower balljoint should be level at ride height. The suspension should work up and down around that. I would just set the ride height where you think it should be . If that's a 46mm for the "Z" dimension, then set it there. If you want the a-arm level, set it there...that's where I set it. You can always adjust it from there if you want to....as long as you align it at that new height.