steering and suspension Coilover Converstion

[Windsma]

Still waiting on parts but,

I have the GC coilover conversion kit on the way.

Front 250lbs spring as suggested by GC

http://www.ground-control-store.com/products/description.php/II=16/CA=281

Rear 400lbs spring as suggested by GC

http://www.ground-control-store.com/products/description.php/II=942/CA=102

Part numbers have changed from most search results. So, I hope i'm updating them for someone else.

Front:

Bilstein Sport Rabbit inserts

34-184530 2 30mm Monotube Strut Insert

The Rabbit gland nuts supplied are M50x1.5 and will not work

Bilstein Gland nut for BMW

B4-B30-U226A1 M48x1.5

Rear:

Unsure which shock, Suggestions?

Will update when i find the correct part number.

80-1868Sport Koni 2way Adjustable.

Edited May 25, 2015 by Windsma

[jmr_1602]

I think GC uses koni adjustable shocks. The rears are not a coilover conversion. Just an adjustable height adjuster.

Sent from my iPhone using Tapatalk

[Windsma]

Correct. 

I was looking for other applications.. like those mentioned here

http://www.bmw2002faq.com/topic/123697-koni-adjustable-dampers/

[TobyB]

If you're running Bil sports in front, then either Bil sport or HD.

 

Be careful not to get a stiffer shock in either rebound or compression, or you'll get

some awful transition effects in heavily loaded bumpy corners.

 

Also, you will find that #400/in in the rear is really really stiff- GC likes

to keep front and rear wheel rates similar, and from experience, I disagree.

Works great on the E30, not so well on the 2002.  

 

whut I tink,

 

t

[FB73tii]

Windsma--I have been running Bilstein Sport front and back with my setup (described below) for several years and like the way they handle.

 

Also, you will find that #400/in in the rear is really really stiff- GC likes

to keep front and rear wheel rates similar, and from experience, I disagree.

Works great on the E30, not so well on the 2002.

 

Toby--what rates do you like to run in the front on your track 2002? I've been running 425lb front (2.5" I.D.) and 350 rear (5" I.D.) for quite some time and like the balance. Weight without driver is 2000lb. I am making some new front struts using larger diameter tubes so I can run the Koni yellow SA's. Am thinking about 450 lb for the front, but have not ordered the springs yet.  Thx--Fred

Edited May 1, 2015 by FB73tii

[Windsma]

Thank you,

I even questioned the 400 rear when buying them from GC. They assured me thats what everyone buys...  And can be exchanged later if I dont like them. 

We have built a few coilover setups here at the shop. Even our 65 Fastback uses 300's in the rear. 

[KIRIEIW]

Has anyone writen a write up on a DIY conversion yet?

[Windsma]

I've watched this vid several times. 

Should be similar. 

 

[TobyB]

Yeah, it's been hashed out a few times.  But with the search, you could dig up the several threads and make a FAQ for it

because it doesn't look like there is one...

 

Fred, for a track car I think I was running 325f/300 rear with Bils sports in front and back.

 

On the race car, I never went past about 450 front/400 rear, and at Seattle, which was really bumpy,

400/350 worked better- and that was with Koni single yellow in front, Aldan doubles in back.

There was a lot left on the table, there, I think.  Maybe I'll go back and find out in a few years.

 

t

[KIRIEIW]

I actually used that video for a reference when I did my e30, however I didnt trim the housings (so there full lengh with welded on spring perches from GC). I'm about 90% fully adjusted down on that car, and I'm not hitting the bump stops (unlike my prior eibach/ billy HD set up), any reason why your really NEED to cut the housings shorter on these cars? Are they more prone to bottoming out and hitting the bump stops?

 

 

-Kevin

Edited May 1, 2015 by KIRIEIW

[Windsma]

Kevin, From what I've read, the shorty inserts have almost the same travel, just shorter insert. 

Cutting the tube is another way to lower the car 2in

I'll post length specs when I find them again.

 

 

 

VW A1 RABBIT
P30-023 Bilstein
12.5" tube length (approx.)
travel= 4.6" + bump
2560 N jounce
725 N rebound

BMW 2002
P30-025 Bilstein Sport
17.59" (447 mm) length
travel= 5.5" + bumper
2150 N jounce
1110 N rebound

 

Pic stolen from BFC

Edited May 1, 2015 by Windsma

[absorbantnut]

Below is a link to a post in my thread where I made my coils. I shortened the housings and have a decent amount of pictures showing how to do everything. I suppose I could post up few more pics and do a DIY. I'll also be reinforcing the rear shock towers & trailing arms as well, I'll post those pics in my build thread.

 

 

 

 

http://www.r3vlimited.com/board/showpost.php?p=4397096&postcount=139

[TobyB]

You want to shorten the housings a couple of inches.

 

Otherwise, you start to run out of travel.

 

t

[M3M3]

Of course, conversations about spring rates are not all that useful without the context of sway bar size, car weight, tire type, track surface, driving style, etc. It is all a system.

[TobyB]

Well, yes, after a point, I agree.

 

At first, though, just based on the initial conditions

(front sport, #250 spring)

you can pretty categorically rule out a whole bunch of other things!

 

(like rear Koni triples!)

 

Honestly, I'd say a #250 is too stiff for Seattle streets and too soft for the track.

But that's my prejudice!
 

 

t