Adjustable upper control arm opinions.
It should also be noted that the spindle height is not the only difference between the A body spindles and the FMJ (and B body) spindles. This footnote has been lost out of the online article I linked above after all the magazine buy outs and website format changes, but the later spindles also have more build in SAI, and are 3 lbs lighter. The increased SAI also tends to make cars MORE stable, so, the later spindles should cause LESS wandering in a like to like comparison with the earlier ones.
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Interesting. When I measured my F-Body spindle to make my layout, I didn't notice the UBJ hole being further back from the face of the spindle. Assuming that is how they changed the SAI. I will have to look into this further.
The bottom line is, all suspension geometry is a trade off. Improving one thing usually happens at the detriment of another, and car set up, use, and driver preferences end up having a large impact on the "best" geometry.
Completely agree with that. It's one of the reasons I have struggling with a direction, everything affects everything else and I couldn't figure out which way to go.
In my mind, there are two competing branches to "suspension design". I put that into quotes because I'm not truly doing any design work, only modifying the current design to see if I can make it better within my self imposed constraints. Suspension tuning seems to have two camps, one that feels stiff springs and small sway bars are better and the other that favors big sway bars and lighter springs. In the same way, this theory has two camps as well, one that favors a low roll center and the other that favors a short roll couple. In the end, I am settling into the low roll center camp, but I'm not ready to say I am in the right camp and any other designs/ideas are wrong. Only that it's the direction I am going. I have reasons for it, but I don't have application or proof.
I will say that I feel like I am in good company in the camp I have decided to apply for residency in. The guy that finally flipped the switch for me designed the late model GT40 suspension, and as I said above, the companies that I respect as actual handling companies seem to be in that camp as well. Not companies that came up with a suspension kit and want to say it handles better because it has coil overs, but one's that (in my opinion) actually tried to make something that would handle and had that as the focus of the design. Too many suspensions on the market now seem to say they "handle better", or are assumed to, when the reality is that handling wasn't even on the radar until the news release was written and the sales group wanted to use it as bullet point.
I am not saying a short couple suspension design will handle like a boat, nor that a low roll center design will be a sports car in every sense. The difference between the two might not even register on the meter for someone without a ton of experience. Heck, it might not even make a difference to someone with a ton of experience. I think it is the better design, but the real world might shrug and say "big deal". And I am only looking at this in a static view, I have no idea where it would go if I had a dynamic view. All I am settled on is that I think a low roll center has the potential to handle better in a corner, so that is the direction I will be building in.