I think I'll keep a close eye on the wing with a rear facing camera for the first few runs and watch for deflection. If it's too bad I'll pull it off and wrap it in carbon which should stiffen it up. I also want to change the end plates and make them longer vertically which should make the wing more effective at speed.
The lower coilover spacers are the racers edge pieces, expensive but worth it. There's about a 1/4" (8-10mm) of clearance on the trailing arm and I ran It from full droop to full compression and the spring never gets close enough to worry about.
The QA1 can be run inverted without issue according to the tech I spoke to however the adjustment knobs are a bit harder to reach behind the big wheels. I thought they were only rebound adjustable like most other single adjustable shocks but apparently they adjust rebound and compression together. The model # is DR4855B for the promastar single adjustables.
The springs are 2.5" (about 65mm) in diameter, and set for maximum ride height right now, which gives me no room to increase spring pressure at a rear corner if I needed. Right now I've got 2" of droop and 2" of compression which is about perfect, but I'll probably be increasing the spring rates quite a bit. I'll probably switch to a 9" spring for more tuning room and move up to a 450# spring for the rear and a 350# spring for the front for a new race setup.
I found a quick (rough) spring calculation from a rally group to get spring rates. First, find your corner weights, for me it's 435# in front and 610# in rear (just the heavy side right now). Now multiply that by the max g-force the car will see, typically 2.5g's in road racing, so that's 1088# and 1525#. The bug isn't so light at 2.5g's
Now take that heavy number and divide it by your suspension travel, in my case 4" front and rear so that's now 272#/in. in front and 381#/in. in the rear that are needed to take up that kind of weight in the corners. Not done yet though, that gives you spring rate but you need to find the effective wheel rate to make this work right. For 944's it's 90% in front and 60% in rear. What that means is if you compress the rear trailing arm 1" the spring will only compress .6" so you need a stiffer spring to make up the difference. So you multiply your front spring rate by 1.1 and the rear spring rate by 1.4 which gives you 299#/in. in front and 533#/in. in rear.
All this calculation is based on my last weigh in but none of these values are current. Since I last weighed in I moved the gas tank, gutted the car, moved the battery, and added more weight to the rear with the oil system and turbo kit. I'll re weigh the car once everything is sorted and order new springs then.