Ground Control suspension

[onenicebimmer]

Hey guys, well I think the day has come for me to finnaly upgrade my suspension. I have been looking around, and it seems that GC would be the perfect thing. I use my BMW for daily driving, AutoX, Driver Schools, and Drifting events. I was looking around, and here is what I found. I was wondering if these compounents would all work together, and if I'm missing anything important:
GC coil-over conversion kit for E30- $399
Koni single-adjustible shocks- $520
Anything else I should add?
Also, what would be some good spring rates (I don't mind back aches), and how low do GC lower in the lowest setting?
Thanks
PS; this is for an 86' 325 ETA

[Jon325i]

The only other items I can think of are some GC camber plates (if you feel having that much suspension "tunability" is necessary) and some rear shock mounts. For the latter, the OEM parts (even E46 M3 cabrio ones) have their limits. I know GC has some of their own design.....I don't have any experience with them so I can't offer much feedback.

As for the spring rates, talk to Jay at GC and discuss your needs/wants as far as what you do with your car. With the Koni shocks you want to get I'm sure he can set you up. A friend of mine has an '87 325is with GC stuff: springs are 450 front & 600 back with Bilstein Sports. This set up is pretty firm.....probably more than most folks would consider for street use (i.e. daily driving), but there's very little body roll in the corners. Seeing the Konis you want are adjustable, you could definately go with a less aggressive set up than my friend has.

In terms of ride height, that's a personal taste issue. If you like the look of you car slammed to the pavement, the GC stuff will let you drag your catalyst converter all day long. Ideally, you want to have a slight front-to-rear rake to the ride height. 1.5" in front and 1.25" in back is pretty common and its a height that makes it 'livable' for the street.

Jon

[onenicebimmer]

Thanks for the reply.
I was looking at the Ground Control website, and it mentioned that the front inserts are for 45mm strut housing only. Does this mean that I have to buy another or will mine work (stock 86 325e housing)?
I also asked one of my friend about the spring rates (he has also been looking in to getting GC) and he said that 450/600 is very popular among the dual purpose bimmers.
Thanks for the info, I'll give GC a call tomorow 8)

[Mystikal]

GC "street" rear mounts ($98 IIRC) are all you're missing.

The amount your car will lower completely depends on spring length, which you can discuss with Jay.

[Bryson]

~375/475 is more popular by far for dual purpose than 450/600 from what I've seen

[aaron_silva]

I have a 450/600 setup (but on a cabrio) and it is a little tough on the street. Luckily, I have good roads where I live.

Aaron

[grapedrink]

$339 from MPactmotorsports.com on the GC stuff.

[onenicebimmer]

wow, those are some great prices. All the GC things are cheaper from there, than from GC.
Thanks for the help

[aaron_silva]

I think because this guy (racing suit)...


...is Dale. He works at ground control.

Aaron

[onenicebimmer]

aaron_silva: Do you AutoX your car? If so, was there a significant difference in your times dropping after the instalation of GC? Would you get different spring rates if you could, or are these "perfect"?
Thanks

[B3ND3R]

Re: Ground Control suspension

Hey guys, well I think the day has come for me to finnaly upgrade my suspension. I have been looking around, and it seems that GC would be the perfect thing. I use my BMW for daily driving, AutoX, Driver Schools, and Drifting events. I was looking around, and here is what I found. I was wondering if these compounents would all work together, and if I'm missing anything important:
GC coil-over conversion kit for E30- $399
Koni single-adjustible shocks- $520
Anything else I should add?
Also, what would be some good spring rates (I don't mind back aches), and how low do GC lower in the lowest setting?
Thanks
PS; this is for an 86' 325 ETA

I dunno if you have bought yet, but since I am considering the same set-up I have been checking prices, too.

After reading this thread and others here, the best I came up with is:

• GC coil-over kit from Mpact Motorsports (obviously) = $339 + $17.38 shipped to me
• Koni Sports from Pure Motorsport = $496.96 w/ free shipping. I've heard of people getting these about $50 cheaper, but haven't been able to find that kinda price, yet. Plus, if you deduct the shipping (about $20) that's $475 or so.

That comes to $853.34 to my door, which is not quite as good as some people have done in the past but still pretty good. 8)

[Mystikal]

Add the GC rear mounts to that price (~$90-100). You'll thank me later.

[808BMW]

Yeah, stiff springs and firm shocks will beat the crap out of stock RSM's.

[aaron_silva]

aaron_silva: Do you AutoX your car? If so, was there a significant difference in your times dropping after the instalation of GC? Would you get different spring rates if you could, or are these "perfect"?
Thanks

Havnt autoX yet. I think my spring rates are fine. I have lived with them for 1.5yrs. Either way, it is cheap and easy to change your rates if you are disatisfied.

Aaron

[onenicebimmer]

Re: Ground Control suspension

Hey guys, well I think the day has come for me to finnaly upgrade my suspension. I have been looking around, and it seems that GC would be the perfect thing. I use my BMW for daily driving, AutoX, Driver Schools, and Drifting events. I was looking around, and here is what I found. I was wondering if these compounents would all work together, and if I'm missing anything important:
GC coil-over conversion kit for E30- $399
Koni single-adjustible shocks- $520
Anything else I should add?
Also, what would be some good spring rates (I don't mind back aches), and how low do GC lower in the lowest setting?
Thanks
PS; this is for an 86' 325 ETA

I dunno if you have bought yet, but since I am considering the same set-up I have been checking prices, too.

After reading this thread and others here, the best I came up with is:

• GC coil-over kit from Mpact Motorsports (obviously) = $339 + $17.38 shipped to me
• Koni Sports from Pure Motorsport = $496.96 w/ free shipping. I've heard of people getting these about $50 cheaper, but haven't been able to find that kinda price, yet. Plus, if you deduct the shipping (about $20) that's $475 or so.

That comes to $853.34 to my door, which is not quite as good as some people have done in the past but still pretty good. 8)

Now, is there a difference between the $660 Konis from GC, and the $496 Konis that you mentioned? seems like a big price difference.Do the GC sleevs fit over both? Is one of them dramaticly better (both have the life time warrany)?
I found the RSMs for 89.99, that looks like a good price.
thanks for that info.