Quite often there seems to be some sort of discussion on front upper control arms (FUCA), the twist that occurs on them during full suspension travel, and who's latest FUCA design addresses the issue the best... I made this study of front suspension motion in 2d a long time ago before I made some upper control arms for my own Z. The study is laid out as top and side views at three different angles - 1) (Right) inline with the lower control arm (to view caster changes during suspension travel)
2) (Center) inline with the upper control arm (to view the twist induced on the FUCA during suspension travel) 3) (Left) perpendicular with the lower control arm (to view camber changes during suspension travel) Setup: Full OEM shock travel is roughly 5.9311". Bump was set to 2.4311" and droop was set to 3.500" (aftermarket coil-over shocks are much shorter with only about 3.5" full travel, so the effects on angularity will be less severe with coil-overs). Ride height is in black, bump is in red, and droop is in blue. Single axis pivot points are defined as small circles, multi-axis pivot point are defined as large circles. Some assumptions were made such as the FLCA being parallel to the ground at ride height, and lengths and angles are best estimates.
Here's an overall view of all three angles. I've zoomed in on each angle for closer viewing below this.
________________________________________________________________________________________________________________________________________________________ Below: Inline with FUCA to view how much twist is induced into the FUCA. Roughly, +0.43° at bump and +0.85° at droop. 
________________________________________________________________________________________________________________________________________________________ Below: Inline with FLCA to view caster changes. I didn't dimension the drawing here, but caster changes +1.0° at bump and +2.5° at droop. 
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Below: Perpendicular to FLCA to view camber changes. 0.43° at bump and 0.96° at droop. 
Conclusion:
Yes, the FUCA is exposed to a twisting motion during full suspension travel. I would imagine it shows itself the most with FUCAs that feature a single adjustable threaded link between ends when the adjustment jam nut has not been tightened enough to prevent becoming loose from the twisting motion. I went on to build a set of adjustable length FUCAs with solid bushings (no multi-axis pivots), confirmed full suspension travel without bind, and have not worried about the twisting motion since.
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Front upper control arm twist during suspension travel - 
