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Discussion Starter #1 (Edited)
Greetings all.

I finally got my dream car a couple of months ago.

00 MY, 74k miles. Still learning how to drive her properly :wroom:

Still has the OEM suspension at this point, which is totally shot. On top of that, my rear sway bar bracket is broken (will order Dinan). I basically want a near stock ride but improved handling. Car currently rides worse that my Volvo 850 did with 165k on the clock. Very unstable, and loses traction on major road irregularities.

Here's what I'm considering:

Bilstein PSS9 Coilovers @ stock ride height
GC Coilvers @ stock ride height
Koni adjustable shocks with stock springs.

If I go with Konis, I would put two rear wheels in the front and maybe camber plates. Which one of these options sounds like the best setup in this case?

Do any of you guys in Los Angeles have GC or Bilstein on the car so you can give me a test drive?

Cheers...


Anton
 

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Challenge Motorsports said:
Greetings all.

I finally got my dream car a couple of months ago.

00 MY, 74k miles. Still learning how to drive her properly :wroom:

Still has the OEM suspension at this point, which is totally shot. On top of that, my rear sway bar bracket is broken (will order Dinan). I basically want a near stock ride but improved handling. Car currently rides worse that my Volvo 850 did with 165k on the clock. Very unstable, and loses traction on major road irregularities.

Here's what I'm considering:

Bilstein PSS9 Coilovers @ stock ride height
GC Coilvers @ stock ride height
Koni adjustable shocks with stock springs.

If I go with Konis, I would put two rear wheels in the front and maybe camber plates. Which one of these options sounds like the best setup in this case?

Do any of you guys in Los Angeles have GC or Bilstein on the car so you can give me a test drive?

Cheers...


Anton
If you can drive or ride in someones car setup with those options, that would be the best way to judge what suits you. I have the Konis and shorter springs as part of the Dinan setup, with camber plates and adjustable sway bar, and I think it is a great street setup with almost no body roll. The coilovers are on a few cars and once properly set up, the owners seem very pleased. Haven't seen the PSS9 on our car, but maybe someone on here has it on the M5 and can opine for you.
As for brackets, both member TCM and Daniel (Beastpower) make good replacement brackets.
Enjoy your new ride!!
Regards,
Jerry
 

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H&R has a coil-over package available. Several threads here refer to that. Waiting for more feedback.

The only final choice for rear sway brackets are the ones from BeastPower.

Enjoy your Beast :M5launch:
 
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I would go with KW Coilovers and of course our rear sway bar brackets. Visit www.beastpower.com for a lot of unbiased product information and pricing.

Cheers, Daniel.
 

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Challenge Motorsports said:
.......74k miles. Still has the OEM suspension at this point, which is totally shot. my rear sway bar bracket is broken

I basically want a near stock ride but improved handling. Car currently rides worse that my Volvo 850 did with 165k on the clock. Very unstable, and loses traction on major road irregularities.

I would put two rear wheels in the front and maybe camber plates.......

Which one of these options sounds like the best setup in this case?

Anton
Let's break this down.....

1) Your suspension is totally shot and it handles worse than a Volvo with 165K miles.

2) You want near-stock factory ride.

3) you want improved handling.

4) You are intending to install 9.5" wheels on the front.

------------------------

My followup questions:

1) Please clarify your comments above #2 & #3. Do you want ride quality similar to a showroom-new E39 M5? Do you want improved handling compared to a showroom-new M5? It's apparent to me that most anything would ride & handle better than your car does now, so I'm very unclear if this should be a repair job or modification project.

2) How much race/open track time or severe duty street use is this car going to see? This will directly influence how stiff the suspension should be and whether various coil over kits with high spring rates make sense.

------------------

Without knowing your answers to these followups, I can safely make a couple observations...

1) Your apparent desire for stock-ish ride height would facilitate (allow) generous jounce and the use of modest rate linear springs.

2) You mentioned a desire to maintain near-stock ride heights. The KW setup has a very different goal. It combines radically progressive rate springs with high tech dampers to allow very low jounce travel and ride heights.

3) The PSS9 is a fairly serious track-worthy performance setup. It will not offer ride quality that favorably compares with BMW M calibrations or factory M springs with Koni shocks & struts.

4) The very best ride quality will be obtained with Koni shocks in conjunction with factory rate springs at stock ride height.

5) I strongly suspect you have no clue how well a healthy factory M5 rides and handles, so you have no reasonable benchmark. It is very difficult to wisely judge what modifications are appropriate under these conditions. It is clear that your suspension is worn out mush and needs repaired.
 

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It sounds like a dinan stage 2 setup would serve your needs as well. Nice ride, better than stock handling, (and certainly better than worn out stock) and similar ride height.
Mike
 

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Discussion Starter #7
Well...it sounds like Koni/Stock setup would be the best for me, but then I still want to take a GC car for a ride. Apparently Dinan camber plated are not that great, and raise the car 3/8" if I use the stock springs.

Does anyone know if GC camber plates will work with Koni shocks?

Any guys in LA with GC or Koni setup? I'll buy you lunch if you'll take me for a ride. I'm in San Fernando Valley :D
 

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Challenge Motorsports said:
Well...it sounds like Koni/Stock setup would be the best for me, but then I still want to take a GC car for a ride. Apparently Dinan camber plated are not that great, and raise the car 3/8" if I use the stock springs.


:D
I have the Dinan camber plates with the rest of the suspension, which has lower springs to compensate. After getting them installed properly, there is a noticable difference. The front end sticks so well I have not had to go to 9.5's on the front. Of course, this is on the street, track is a different story. Plates got about .75 degrees more negative camber. If you don't get the camber plates, go with 9.5's on the front (3mm spacer and longer lug bolts available from Luke @ TireRack).
Regards,
Jerry
 

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Challenge Motorsports said:
Does anyone know if GC camber plates will work with Koni shocks?
Actually.....the GC kit comes with Koni shocks that are same as you can buy elsewhere (Dinan, Shoxdotcom, Tirerack etc). That said, GC's kit pricing is very competitive, such that the Koni's they offer in kit form (or separately) are sold with very little price markup.

Confusion about compatibility of Ground Control upper strut mounts stem from the fact that the GC strut mounts were originally designed to work with the unique GC upper spring perch.

The GC coil over spring configuration uses a smnaller diameter spring. It is nothing like OEM or aftermarket OEM-ish offerings like Dinan or H&R 29441 spring.

The factory upper perch setup uses a plastic ball bearing turntable that allows the perch to rotate with the Koni. This "oddball" turntable gizmo mounts on the factory upper strut mount. As such, the factory BMW mount has provisions for the perch turntable. GC setup is different, so compatability can not be "assumed".

It is rumored that GC now offers more than one upper strut mount to fit E39 & they may have one for OEM perch turntable fitment. I have not confirmed this. Your best bet might be to call GC and ask them if they'll sell you upper strut mounts and Konis to fit your stock springs. This should set you back around $500 (frt camber adj strut mounts) + $750 (koni's). GC will not sell this combo if it doesn't work! I'm sure they'd rather sell you the complete coil over kit with adjustable mounts though. I think the complete kit goes for around $1900 for coil over system with Konis plus another $500 for frt camber adj strut mounts.

Let us know what you find.
 

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as we chatted about then, I guess going with JUST Koni Yellow's to start is a good piece meal approach to tweaking the suspension.

You could then decide whether or not you wanted to go the GC or Dinan route.
 

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adelaide said:
as we chatted about then, I guess going with JUST Koni Yellow's to start is a good piece meal approach to tweaking the suspension.

You could then decide whether or not you wanted to go the GC or Dinan route.
The piecemeal approach is a cost-effective approach from a "parts cost" perspective. You can reuse Konis...plus they are real hot items used on ebay. A backyard mechanic can't go wrong with this approach.

The drawback to this gameplan is almost "double" labor fees, if you farm out the work & wind up changing springs later. If the latest GC strut plate design allows various spring systems (OEM & GC), I think they'd be a no-brainer purchase too. You will need to research that, if you're interested in optimal grip/alignment. As other's have noted, additional negative camber is a godsend.
 

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Lscman said:
The piecemeal approach is a cost-effective approach from a "parts cost" perspective. You can reuse Konis...plus they are real hot items used on ebay. A backyard mechanic can't go wrong with this approach.

The drawback to this gameplan is almost "double" labor fees, if you farm out the work & wind up changing springs later. If the latest GC strut plate design allows various spring systems (OEM & GC), I think they'd be a no-brainer purchase too. You will need to research that, if you're interested in optimal grip/alignment. As other's have noted, additional negative camber is a godsend.
Some more great advice, thanks again.

As I'm sure like others on the board, with the E60 M5 looming on the horizon, or just having such a high mileage car, I am not 100% sold on putting in thousands for suspension mods now.

GC might sound like the most moderate, complete set-up with some degree of adjustability then.

Koni's sound like the most cost effective, bang for the buck, yet limited change. Probably a good stop-gap choice.

I would assume the addition of the rear anti-sway bar as you mentioned would be a positive, low-cost value as well.
 
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