so, i put the threaded collars on my bilstein shocks today and i made a few observations.

can anybody please confirm/deny any of this:

- collars seem to be "tapered" inside, the bottom part has only a small amount of play while the top moves at least 1mm side to side

- the bottom of the collar DOES have some small amount of play. this concerns me as the "ring" it sits on is tiny and has to support the whole weight of the car.
is this normal ??? (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif)

(IMG:http://www.914world.com/bbs2/html/emoticons/givemebeer.gif) Andy

pic might help ...

at the top (#1) about 1mm side to side, at the bottom (#2) a small amount of play ...

should i worry? i remember that grant had a threaded collar jump over the retainer ring!
(IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif) Andy

werd... mine are kinda loose too...

but the original lower perch used the same ring.....


damn... scary.

AA

(IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif)

The threaded part slides over the shock, so there has to be some room for it to move or you wouldn't be able to slide it over. Shock bodies are not a guaranteed machined true cylinder, after all. The bottom of the collar (actually a point near the bottom) rests on the ring around the shock, yes? So it would have less movement.

The phenomenon sounds normal. I would guess (SWAG!) that the amount of play is also normal, but I am not at all sure on that.

--DD

The Bilstein spring perches have an indent on the bottom of them. Once the perch is pressed against the ring, it becomes impossible for the ring to expand and come out of the groove in the shock. The threaded collar doesn't seem to have this indent... That is is what would worry me the most, especially with the play that could allow the threaded collar to move back and forth and eventually work the ring out of its groove.

Pic:

QUOTE (bondo @ Jan 22 2006, 09:11 PM)

The threaded collar doesn't seem to have this indent...

mine do. there's an indent of about 1/2" deep, then a sharp "edge". this edge is what sits on the retainer ring and this *should* prevent the ring from expanding and working it's way out of the groove ...

but, my real concern is the fact that the bottom of the collar is not at all a tight fit on the shock. there still is some side/side movement at the bottom right where it sits on the retainer ring. (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif)

the original bilstein bottom perch is a real snugg fit, in fact, i had to use a hammer to get it off the shock.

on the other hand, the new threaded collars move freely over the shock and rotate freely as well. the bottom play is "feelable" but less than 1mm side/side.

i am worried that the whole collar will jump over the retainer ring and the shock will fall down 8" while i'm driving!
(IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif) Andy

Yes, the OD of the shock is smaller that the ID of the collar.
As I recall, the 1 mm is about right, but closer to .060. It seems less below as the keeper ring is a better fit. If you don't shim the collar/body interface it may get screwed up from going off center and working by the keeper. I used plastic shim stock cut to wrap around the shock body....full length, keeper to top of collar.
One layer of .020 & another of .010....but it may have been .005. A pair of calipers is your friend here.

I'm more surprised that you didn't complain about how the spring hat fits. I had to do some serious rework to make the top fit properly. These are from Colman.

A pic of mine

As you mentioned I have slid a collar over my rear Koni's. In researching, the company in question mistakenly sent wrong collar diameter (they actually picked wrong part into a bag with differnt part number). It was close enough to get by an expert 914 guy who installed them on my car. I would reccomend taking inside diameter measurements and calling them to confirm you have correct diameter if you want to be extra safe.

The wrong diameter on my Koni's allowed similar play you are talking about. The correct collars they supplied fit much better with very little free play at the bottom with some at the top.

I have colman coil spring perches. I flipped mine over and had then machined to the size if the indent on the orginal perch, then I put a shim on the top. Remember at load the assembly will not move. I am planning to put a thursh bearings and washers assembly to aid in the the turning of the nut.

Mar7ck

That is true, but the overlap is the same all around, rather than being offset to one side and risk getting it cocked in the bore......but hay, as one stubborn German to another, do what you want.
I haven't had any problems with it as is and am running stiffer springs that you presently have.......tho you'll get there eventually.

Hmm, you could always cut the center out of the stock bilstein perches and set the threaded collar down on that. (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)

Same situation here. I was anticipating tighter tolerances between shock tube and collar. It worried me a bit, but (knock on wood) now I've done quite a few track events and hard driving with no issues. So I guess it is normal but sure is disconcerting to the newbie installer. I have used two different top hats, both from Coleman, one cast and one machined billet and both versions fit fine. (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

yup, I like the flip them over idea....

Time to visit your favorite machinist....

bring some hair stuff and a baby gift.

Rich