Here's what I did.... very long (archive)

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Well guys, the suspension have been installed susccessfully!! With help from my buddy Tom (oversteerdawg on miataforum.net, and a lil cutting assistance from another buddy Kurt ('95 SC miata, also on miataforum.net), the Bilstein sports, Ground-Control coilovers (450fr/300rr), and GC camber/caster plates have finally been mated with the e28. The results... absolutely beautiful. The install went without snags, except for an unnecesary rear-interior removal (and thus re-install) (ahem...Raj...). The step that took the longest was the modification (cutting) of the strut towers so the camber/caster plates can fit and move (for adjustment). Since it was Tom and my first time cutting sheet, we went into the job a little 'nervous'/anxious (but in retrospect, it wasn't that bad at all, just make sure to go slowly). -While in the process of cutting, we even thought of a way to possibly get a strut brace to work with this setup (ED, have you fitted a strut brace with the GC plates? your input would be much appreciated). Anyways, that's the next upgrade. now for the road testing.
Keep in mind that as of now, my AVS-Intermediates (225/50) on e31 cross-spokes (often refered to as 'basketweaves') are not ready yet. -Damn UPS ground, too slow! but should be on by tomorrow. So for wheels/tires, i'm running stock 14 inch wheels with some 205/70 $hitters... Dayton Daytona!! (>450 treadwear!) hahaha. but we cranked them to 40psi for our test drive and here's my thoughts:

Before I rode in the car, I had doubts about the selected spring rates that Jay at ground control chose. 450 fronts and 300 rears, I initially had my doubts, but after some discussion/thought/research with Tom and Kurt, I rested assured that it will be correct for the e28. (afterall, it is less extreme than Ed's current setup! -you maniac. lol). First off, man, talk about response. With every steering input, there was a noticable result in change of direction. Before my car used to tilt and lean in that direction, but tracked straight ahead like i was driving a boat, looked/felt like my car was 'waddling' down the street, now it's a flat car making subsequent changes of direction. -Very impressive! Bumps, and rough roads aren't even harsh (imo), but rather like a really firm suspension properly absorbing the impact. -Those Bilsteins have the compression and rebound damping necesary to control the heavier spring rates. With 4 people in my car, the car did NOT at ANYTIME hit the bump-stops, even under cornering forces...very very impressive. And because the Bilstein sports have the proper damping, there was no 'wallow-y' ride associated with under-damped suspensions; the balance of the car was not upset due to bumps, ROUGH pavement or combination of both with corners! I think it's easy to tell that I am very VERY satisfied with my setup and I have zero hesitations about recommending any of the products I've got. When I first received the parts and were inspecting them, my buddies and I were extremely impressed with the build-quality and care in preparation and from there on, I felt "redeemed" in that I "got what I paid for" (in terms of quality). And with such high quality and attention to detail, I further rest assured in being satisfied with the chosen spring rates. -If your on the board Jay, THANKS!!!

It was definatly a large investment, but here's how I rationalized my choices:
-my goal was to have a sharp handling e28.
-Handling was priority 1, ride comfort was a distant second.
-Coilovers vs ordinary Springs: It came down to HR's for $220 with a progressive spring rate thats at ~200lbs/in and a 1.25 inch drop fr/rr (according to turner motorsports) VS. GC coilovers, which were $180 more, using Eibach ERS springs (so if I wanted to change spring rates, I just buy a set of ERS 2.5inch dia. springs). I felt that the added benefits: ability to corner-weight my car, thus making left turn and right turn handling the same), adjustable ride height (no worries about oil pan), and the 'customized' spring rates of the GC's were worth the extra 180. Ohyea, the convenience of the coilovers during the install eliminated the need for spring compressors (during the assembly process), a HUGE plus.
-Camber/caster plates: as my buddy Kurt pointed out, our cars are 14+ years old, and that means our cars are probably not perfect (in terms of body/frame chassis etc) in alignment. The added benefit of adjustability, especially going to bigger wheels and different suspension, will allow me (actually the alignment shop) to make proper corrections. Again, I felt that adjustability/correctability was worth the extra cost, $299 for the GC kit (fronts only) vs. ~200 for OEM stock mounts that offer .5 degree of neg. camber. -think about it, would you pay 50 bucks to have camber/caster adjustability for each corner of your car? I would/did. =)
-Bilstein sports: pretty simple here, I don't think I need to write anything about them. Thanks to Erik in PA, the source for my Bilsteins. They work awesome in this setup.

Now here's my reasoning for dumping all this cash into suspension while leaving my stock super-eta motor alone. The prev. owner religiously had the dealer maintain it until I had the car (I have the window sticker and all the
records) and many of the gaskets/seals on the motor have been replaced within the past 35k mi. I figured when I take my car to a track, It's more wise for me to take people in the corners and carry more exit speed rather than trying to out-power people in the straights. -the turns are where the fun stuff's at, straights are just that....straight (imho, boring. at least in an NA e28).

Also, by upgrading the suspension, I've added "active safety", the ability to manuver AROUND obstacles rather than just braking into them (stock bmw's are already pretty good, but try it at higher speeds and it can get hairy, esp with a 14+ year old car). Even if I have to rely on braking, the balance of my car's been much improved (or sustained) during braking, no more dive! which means my brakes are probably working more effectively in stopping my car.

Anyways, just wanted to put some thoughts out there on the board for anyone thinking about their suspension or wondering how the GC's were for a daily-driver. Hope it was informative and not 'too biased' in terms of exalting Ground-Control, but what can I say, I've tried them, and I INSTANTLY loved them. I believe in the product so much that when my brother is ready to dive into a suspension upgrade on his WRX wagon, it's going to get GC coilovers and the GC Advance Design shocks/struts ($2k total).

****update*****
I now have the e31 wheels and the AVS-Intermediates 225/50 16 at 35psi. Camber is set to neg 1 degree and I have yet to change the ride height, which is quiet a bit taller (2-3 inches) than my friend Raj's car with Bilstein sports and HR's. I LOVE the ride and more so the handling. there's minimal body roll, and this is with stock sways. anyways, i'll add more later

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