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      04-22-2009, 05:41 PM   #23
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Do it! I loved my GC's track/school kit on the old E36:





They total transformed how the car felt - granted the previous oem suspension was 'well' used prior to my install. I'd love to see the results with a Z4M cooop.
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      06-16-2009, 03:10 PM   #24
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Quote:
Originally Posted by OutOn View Post
Finishing conversations with AST. I´m mostly convinced mainly because the price is so much cheaper than the GC kit because they´re using my OEM bits to develop a kit for the Z4M.

I´m still deciding what spring rates to order them with. 500/600 ?
Bump - So what did you do?
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      06-19-2009, 01:33 PM   #25
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I got a new set of springs for my KW V2's from GC. Great customer service.

I'm running 450/650 on mine.
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      06-19-2009, 01:43 PM   #26
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So now you're running fixed spring rates on the KW V2 shocks/struts? Interesting...

The only reason why I never considered KW was because none of their kits had linear springs. Not even the ClubSports!
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      06-20-2009, 03:56 PM   #27
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The front of the KW Clubsports have linear springs. The rears are progressive
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      06-21-2009, 12:30 PM   #28
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Quote:
Originally Posted by pbdm4k View Post
I got a new set of springs for my KW V2's from GC. Great customer service.

I'm running 450/650 on mine.
Did they recommend that, or did you ask for the spring rate?
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      06-21-2009, 04:35 PM   #29
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400 and even 500 seem like really low spring rates for a track orientated set up.
I would have thought people would be going for something like 600 front and 800 rear ?
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      07-08-2009, 11:07 AM   #30
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Quote:
Originally Posted by The HACK View Post
Did they recommend that, or did you ask for the spring rate?
Combination of both. My car is still a daily driver with track day duties, so I can't go all out.

Some streets in Toronto are f**king brutal.

Oh, and my bad, typo on my part, I'm using 400/650 springs.
The KW V2's are linear in the front and progressive in the rear. Now I've got linear springs all the way around.

GC sent me Eibach's for the rear with their own GC coilover perches and H&R's for the front to be used with the V2's helper springs.

These springs are already a bit stiffer than what the V2's are, and going too stiff would be bad for the shocks.

My goal was just to spend as little as possible and get the spring rates more in line with what I'd like out of the car.
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      03-26-2010, 02:02 PM   #31
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Lousy luck with GC parts. First delivery had wrong camber plates installed .
Second delivery was wrong specs, party my fault.
Third delivery had out-of-box failure on a weld @ strut tower stud.

Three strikes. Lots of money, time and labor wasted. Immense frustration.
Their phone support was good but the product just failed hard.
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      03-26-2010, 02:13 PM   #32
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ground control parts failure.

Lousy luck with GC parts. First delivery had wrong camber plates installed .
Second delivery was wrong specs, partly my fault. Rattled as if broken.
Third delivery had out-of-box failure @ strut tower stud.

Three strikes. Lots of money, time and labor wasted. Immense frustration.
Their phone support was good but the product just failed hard.

FYI Broken strut tower stud, broke before vendor spec of 18 lb-ft. Other side was halfway gone in same location. The horseshoe piece flexes too much during install and the bolt separates from the head. IMO the allen-head recess weakens the bolt at the base.

--correction, the "weld" didn't break. The stud twisted off the welded head. ---

Fix involves dropping the suspension, fix/replace part, realign front end.

Attachment 363301

Last edited by blender; 11-21-2012 at 10:33 PM..
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      03-27-2010, 04:39 PM   #33
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video from Ground Control

This is Jay from Ground Control. I was steered to this picture, and I just thought I would say that if this happened to you, we will just send you a new one at no charge.

Click here for observations about torque wrenches


The weld didn't break in the picture, the stud was twisted off right at the bottom.

So, I believe the broken part in the pic above is nothing to be concerned about, they are very difficult to break, and when replaced with a new piece are not a safety problem.


[u2b]<object width="480" height="385"><param name="movie" value="http://www.youtube.com/v/RtbsgoQieE4&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/RtbsgoQieE4&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="480" height="385"></embed></object>[/u2b]

If that link doesnt work, here is video of breaking parts in the interest of science:






Jay from Ground Control
email me from the link on the webpage

Last edited by JM3; 03-27-2010 at 04:56 PM..
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      04-02-2010, 11:40 AM   #34
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Quote:
Originally Posted by rcleme05 View Post
Lousy luck with GC parts. First delivery had wrong camber plates installed .
Second delivery was wrong specs, partly my fault. Rattled as if broken.
Third delivery had out-of-box failure @ strut tower stud.

Three strikes. Lots of money, time and labor wasted. Immense frustration.
Their phone support was good but the product just failed hard.

FYI Broken strut tower stud, broke before vendor spec of 18 lb-ft. Other side was halfway gone in same location. The horseshoe piece flexes too much during install and the bolt separates from the head. IMO the allen-head recess weakens the bolt at the base.

--correction, the "weld" didn't break. The stud twisted off the welded head. ---

Fix involves dropping the suspension, fix/replace part, realign front end.

Attachment 363301
Did you use power-tools? Did you do the alignment yourself?

I bought a set of GC coil-overs used. Prior to the installation I knew there's potential for trouble, it had appeared to me that while the prior coil-over installation was correct (in fact I knew the mechanic who installed it), the subsequent alignment, since the shop that did the original install did not have alignment rack, the guys doing the alignment had over-torqued the nut(s). So of course when I went to install the used GC kit on my car, the weld on the stud broke off. I sort of had an inkling that this was going to happen, because when I received the used kit it had appeared that one of the studs had some damaged threads.

When I get the new plates in and installed, I'm going to have to leave a note with the alignment shop to make sure they PROPERLY TORQUE the strut nuts and do not use power/air tools. Sometimes inexperienced shops will use a power tool or an air tool and even an air ratchet can deliver enough torque to do some serious damage.

Otherwise the GC kit was by a very far and wide margin one of the easiest suspension installs I've done. Took me about 4 leisurely hours spread over 5 days at work, including about half an hour modifying the trunk trim with a Dremel to allow access to the rear shock adjustment.
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      04-02-2010, 01:45 PM   #35
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Quote:
Originally Posted by The HACK View Post
Did you use power-tools? Did you do the alignment yourself?

I bought a set of GC coil-overs used. Prior to the installation I knew there's potential for trouble, it had appeared to me that while the prior coil-over installation was correct (in fact I knew the mechanic who installed it), the subsequent alignment, since the shop that did the original install did not have alignment rack, the guys doing the alignment had over-torqued the nut(s). So of course when I went to install the used GC kit on my car, the weld on the stud broke off. I sort of had an inkling that this was going to happen, because when I received the used kit it had appeared that one of the studs had some damaged threads.

When I get the new plates in and installed, I'm going to have to leave a note with the alignment shop to make sure they PROPERLY TORQUE the strut nuts and do not use power/air tools. Sometimes inexperienced shops will use a power tool or an air tool and even an air ratchet can deliver enough torque to do some serious damage.

Otherwise the GC kit was by a very far and wide margin one of the easiest suspension installs I've done. Took me about 4 leisurely hours spread over 5 days at work, including about half an hour modifying the trunk trim with a Dremel to allow access to the rear shock adjustment.
Gotta love the Dremel. I'm amazed at how many odd jobs I use it for...

Good advice on power/air tools. If you're super concerned you can always hang around the shop (donuts and other goodies do wonders as well--then you're the cool guy with donuts and not the "picky guy with the BMW").
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      04-03-2010, 10:03 AM   #36
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Quote:
Originally Posted by The HACK View Post
including about half an hour modifying the trunk trim with a Dremel to allow access to the rear shock adjustment.

Can you post a pic of what you did to get access? I have to get around to doing this next weekend and I am lookng for ideas.
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      04-03-2010, 10:34 AM   #37
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Quote:
Originally Posted by JCz04Bimmer View Post
So now you're running fixed spring rates on the KW V2 shocks/struts? Interesting...

The only reason why I never considered KW was because none of their kits had linear springs. Not even the ClubSports!
You need to go the 'competition' route for linear springs from KW. The Clubsport suspension is a street suspension.
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      04-03-2010, 03:15 PM   #38
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Quote:
Originally Posted by F360C View Post
Can you post a pic of what you did to get access? I have to get around to doing this next weekend and I am lookng for ideas.
Here's some pics from mine...





I found some plastic plugs from Lowe's / Home Depot that fit the hole I drilled through. You can't tell from the pics (due to the flash), but it looks like OEM.

This is a pic of the passenger side looking down the hole:

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      04-05-2010, 12:28 PM   #39
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Quote:
Originally Posted by F360C View Post
Can you post a pic of what you did to get access? I have to get around to doing this next weekend and I am lookng for ideas.
You don't want to see mine. I hacked away a huge part of the trim just so that I don't have to second guess. Right now the entire shock tower is exposed.
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      04-11-2010, 01:31 PM   #40
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Quote:
Originally Posted by Rick Hunter View Post
Here's some pics from mine...





I found some plastic plugs from Lowe's / Home Depot that fit the hole I drilled through. You can't tell from the pics (due to the flash), but it looks like OEM.

This is a pic of the passenger side looking down the hole:

Can you get at the adjusters with just the koni knobs or do you need some kind of extension?
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      04-11-2010, 09:09 PM   #41
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You'll need an extension. Home Depot / Lowes / etc should be sufficient to find the piece(s)
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