Technical advice for getting Bilsteins revalved

[JGood]

if you want a shorter insert that will otherwise drop right in the ix Koni SA's will definitely handle 450# springs.

Hmm, I didn't really think about that. Why would people use Corrado inserts, including GC using them as a base for their spec stuff, if the iX part fits?

[nando]

if you want a shorter insert that will otherwise drop right in the ix Koni SA's will definitely handle 450# springs.

[JGood]

Well, now this thread has me confused....

http://www.r3vlimited.com/board/showthread.php?t=90481

[JGood]

Yeah nvm Sorry. I researched it.
Anyways, isn't the 8641-1198SPORT the shock GC uses and modifies to pair whatever rates you're choosing?
They are telling you in "stock" form, the 8641-1198SPORT will handle up to 450lbs well?

Yep, that's how I understand it from some additional reading.

And yes, Mark said it would. His words were "handle 450# springs with ease" actually.

[ak-]

Nope, Corrado

Yeah nvm Sorry. I researched it.
Anyways, isn't the 8641-1198SPORT the shock GC uses and modifies to pair whatever rates you're choosing?
They are telling you in "stock" form, the 8641-1198SPORT will handle up to 450lbs well?

[JGood]

Nope, Corrado

[ak-]

Is that Koni part # for the iX inserts?

[JGood]

Thanks guys.

Nando, I think it's correct, someone pulled it from a Bilstein PDF doc which is NLA. Can't confirm. It feels right though, at least on low speed compression. I had a set of brand new 325i sports and 325ix HD's in my hands next to each other. The iX insert took no effort at all to compress, the 325i sport took all of my weight, and still slowly compressed. Terrible test, I know.

I just contacted Ground Control though, and they said Koni 8641-1198SPORT will handle the 450lb springs well. And it looks like it will be cheaper to buy then what it will cost to revalve the Bilsteins. I think I'm gonna go that route. Koni is having some crazy sales right now. Normally $182 for that shock, $138 right now, from tirerack.com

[nando]

I just gave them my spring rates and they were supposed to match it to that. But they came back STIFF. I'm not sure about specifying the rebound/compression numbers instead - you might end up with something more comfortable that way.

I've got the number for them somewhere, I think you just call the California HQ and ask for Raul, but I can't remember if that's his name exactly.

are you sure about the stock ix valving?

[jlevie]

There's a very good chance that Bilstein will have a good idea as to rates if you tell them the car & spring rates. Call them and see.

[JGood]

I have a set of GE coilovers (450f/650r). Front struts are shortened 1", using 325ix Bilstein HD's. Rears are normal e30 Bilstein Sports.

The car is way under damped in the front, it's bouncy and feels like I'm just running coil springs with no shocks at all. So I picked up a blown set of 325ix HD's to send to Bilstein to have rebuilt and revalved.

Here is the Bilstein data I have for a 325i Sport Shock and a 325ix HD Shock:

BMW 325I SPORT FRONT
COLL/EXT: 515.0/597.5
REB/COM: 2330/755

BMW 325IX 4WD F
COLL/EXT: 438.5/511.0
REB/COM: 1365/465

Looks like the IX rebound and compression numbers are about half of what the Sports are, which are probably slightly soft for a 450/650 setup. I'm thinking maybe 2500/900 or so? This is just a street car, will never see a track, but I need it to be able to handle some bumps under aggressive driving. The car weight is 2680lbs, probably 53f/47r or so.

Anyone have any thoughts, suggestions, or experience?



Here is the order form for the rebuild:

http://www.bilsteinus.com/uploads/tx_templavoila/Repair_Order_Instruction_Sheet_04-2011.pdf

It sort of leaves it up to the user to specify the rates... are the above listed numbers what they are looking for? From what I understand, those numbers are Newtons of force required at 52 cm/sec. Is that what Bilstein uses to universally measure and valve shocks?

Anyone have a number for a contact at Bilstein that I could discuss all of this with?