Congrats on scoring a deal on a used set. Whenever I need coilovers, I search for that deal for months, and it never shows up.
Okay, this stuff is kind of like religion, politics, or taste in barbeque, but here's my take on the process.
I run alignment settings pretty much like aeronaut's on my E36. I have swapped hats and one camber shim like you.
People say E36s like front springs that are about 100-150# softer than the rear because of the different wheel rates front and rear. I'm not 100% certain, but I think the dampers GC uses are able to control the spring rates you have. It's more spring than they used to sell with their street/track kit, I think, but I seem to remember they had headroom into the 600's.
I lower the front height so the front control arms just start to slope up towards the wheel side, and then back it off and set the height a little bit higher than that. The front suspension gains negative camber as it compresses, which is good. But I'm told that, as the control arm slope changes direction, the rate at which it gains negative camber is decreased quite a bit. Plus I'm told going too low with struts buries the roll center.
Wedge -- I go for setting up the rear 3/4" higher than the front, measuring the difference at the two jack points. Some times I can get away with more or less but the hard braking gets twitchy if I have it wrong, and it's really easy to tell when it's wrong. Hopefully, I have enough height adjustment on the rears to achieve this angle relative to the front height I just set.
I set all the dampers to full soft, and drive the car for some laps to see if it's rubbing under compression. With 500/600 spring rates and Koesi 17X8.5 ET 40 wheels, it's not likely to rub much. If it's bad, I roll/pull the fenders until it clears fairly well. I don't bother dialing in the fender clearance 100% until I get the damper settings figured out and confirm my sways don't need rebalancing.
A car is flat-out gonna understeer if I'm turning in at too much speed or pinching the exit, and it will flat-out oversteer if don't get my understeer under control PDQ or I use too much throttle on exit when the steering angle is still dialed in. Nothing about coilover adjustments will fix that. I'm just trying to use the dampers to balance the way the car body rolls in and flattens out, so whatever grip I have can be used. For example, if I turn in, and the front of the car gets to it's settled roll position later than the rear end of the car, I will get more understeer than I will have if I can get both ends to roll and set in a coordinated way.
With single adjustables, I go out and do some laps and pay attention to what's happening in the corners. Most likely it is understeering on corner entry, so I stiffen the rear dampers one click (whatever 1/5th of the total adjustment range is) and go back out again to see what happened. Stiffening the rear should allow the front of the car, which will be softer, to take a set going into the turn faster than the rear end, and give the front more grip. But I don't want to overshoot the rear stiffness, because it can lead to rear wheelspin on exit or even unloading the inside rear wheel. If one click isn't helping enough to dial out the understeer, then I try two clicks. And so on.
If I'm getting oversteer on exit, (instead of understeer on entry), then I will stiffen up the front end one click and go back out to see if that's good or I need another click maybe. Lather rinse repeat.
With a light car like an E36 I'm trying to get the minimum amount of rebound stiffness necessary to create even transitional grip balance between the front and rear ends on corner entry and exit. I'm not trying to increase roll stiffness by cranking the dampers way stiff. Springs are for roll stiffness, dampers are for balancing the front and rear to make the car rotate to my unique preferences as a (admittedly lame) track driver.
If I put in one click and things get better, then put in another click and things aren't clearly even better than 1 click, I will usually back off a click and see if I'm still good.
I try to get one end ironed out reasonably well, I write that down, and then see if I can get any better traction out of the other end.
First time through, when I'm doing that second end I often wind up with several clicks applied and no improvements. That's when it's a PITA.
It could be, I just can't get any more from the second end with the setup I have.
Or it could be I have a shade too much on the first end, and if I backed off it a little bit, I could go back to zero on the second end and then work my way up to some happy medium. So I try that. I
f I strike out there, I might zero out both ends and see if it was even possible to get better behavior out of the second end, regardless of how much it screwed up the first end. If I can get some improvement in the second end that way, I write that down and then start seeing if I can get the first end under reasonable control with more rebound and kind of split the baby.
But after all that, I might just wind up full soft on one end and some adjustment on the other end, and that's just the best I'm gonna get.
If I have the springs 100-150# apart and I can't get the car balanced because one end just seems way off, then I have to start figuring out whether I have too much sway bar on the front (leads to understeer) or on the rear (leads to oversteer).
If the car is just too damn twitchy whatever I do with the dampers and it won't settle in a corner, that probably means I have more spring than the dampers can control. So they need revalving, or I need 4 new springs with less poundage.
When I do get it right, it's obvious to me that it's all clicking. I'm not fighting the car and it just flows. Or as much as a hack like me is capable of flowing. If other E36s on comparable tires are just pulling away from me, and I'm trying weird lines trying to find something that will catch up, it's still wrong.
Last edited by JBasham; 03-12-2018 at 10:45 AM.
Reason: Edited bad info about front control arms and camber
If God meant for man to motor-swap LS engines into track cars, He wouldn't have created Corvettes.
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