Koni rear shock questions: foam cylinder and white plastic split washer
 

I just got Konis for the rear on my 968, front's coming soon.

The rears have a little white split washer plastic thing loosely installed on the shaft. Is it trash/packing material, or does it stay? Similarly, the top part of the shock (female part that other end slides into) seems to have a foam cylinder stuffed inside it. Same question, remove, or leave? I've never seen these two features on other shocks that I've replaced in the past. PS: Koni's instructions are garbage.

cheers,
c

Leave them, they are part of the shock.

The foam cylinder is the bump stop. The plastic washer is there to prevent the bump stop from sticking to the shock surface.

White plastic stays. In a front shock, the bump stop may contact this piece while the steering is being turned and it aids in reducing friction under compression that may damage the bump stop. Seems overkill for a rear but it probably makes the bump stop effect more repeatable.

Other part inside sleeve is bump stop that limits travel, you only remove it to adjust shock then reinstall it..

"Some shock absorbers include a bump rubber concealed under the dust cover and it must be removed prior to adjusting."

From Koni 1035 sport shock adjusting procedure Koni USA. http://www.koni-na.com/en-US/NorthAm...-Guides/compb/

T

Dang, I wonder if you guys are as fast on the track....?

Before I could type there were two replies....:thumbup:

T

Thank you gents. Do you guys run them with the factory default setting, or stiffen them a bit? This is for fast street, not track, all suspension on the car is original, I haven't swapped anything out in the last 15yrs. I guessing it's going to feel a little different.

cheers,
c

you might remove the foam, there is a small hole in the top to facilitate this, and make sure the rebound is the same. Fully compress both units, side by side, and adjust as necessary for the same rate/time to get to full extension.

I can't speak for the 968, but on a 1988 944 base i have the rears set at 1 full turn from fully soft and the fronts set at 1 3/8 turns from fully soft. This is with stock springs. I find these settings to be good for normal/spirited street driving. Fronts are adjustable after installation so no issues there. Rears have to be set prior to installation.

VERY good advice. I removed the foam and compressed both by hand and they extended at very different rates. I got them matched very closely, then swapped them out. Took about an hour, I did it on the ground with 2 floor jacks instead of using the lift. The shocks in the car were original from 1993, the undercoating over the top mounting bolts was still intact, and the shocks look prehistoric. The passenger side had staining that looked like a leak, but once the were out, I found them to be quite tight. It took nearly as much effort to compress them as the new Konis. Pretty incredible for 25yo original shocks (160k on the clock). The car has become pretty loose and I was hoping that they would tighten things up, but they have not. Body roll seems the same (excessive) and cornering hard doesn't show an improvement. There is a noticeable reduction in road noise and vibration, so I have a lot less ruckus coming from the rear than I did before. I'll get to the fronts in a few days and I'm guessing that they're in much worse shape than the rears were. We'll see.

I'll order new bump stops and dust sleeves for the front when I order the struts. Anything else needed? I've got a pretty wet and squishy sway bar bushing up front, but I need to get some leaks fixed first.

cheers,
c

Audi49, I used your setting.

thanks,
c

If reduced body roll is your only goal, bigger sway bars, springs, and torsion bars will get you there. I installed all that at the same time as my adjustable konis and the difference was astounding. There are 6 points where the front suspension could feel "loose" like you say: control arm rear bushing, control arm front bushing, ball joint, outer tie rod end, upper shock mount/bearing, and your sway bar bushings. They're all fairly easy to replace while your're doing your front shocks, so if you feel any clunks, play in the steering wheel, or looseness from the front end, you could check them for play.

Thanks Mike. The factory handling of the car when I bought it in 2003 was perfect for me. If I can get back to that or slightly better, I'm happy. I was happy with the oem swaybars before everything wore out, so I'll probably be happy with them again once I finish swapping out worn parts.

cheers,
c

As far as I can tell, these were the original shocks from 1993. I had to force the socket over the undercoating on the top bolts. Bottom bolts were so tight that the snapping noise that they made when they broke loose made me think that I had sheared the bolts.

cheers,
c
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It's not one of the cheaper things you can do to these cars, and it's kind of a lot of work, but if you really want to tighten up the handling, I'd recommend a full rebuild. The factory rubber bushings only last so long. I rebuilt mine, along with new shocks/struts/springs/torsion bars/swaybars, and the difference is night and day.

There are lots of options, from OEM up to metal bushings. I went with harder rubber bushings from Elephant Racing (their "sport" bushings), personally.

I just ordered the fronts. Best price I found was thru Race Consulting Agency. $147.98/ea (Koni Shock - Sport Series (8641-1414SPORT). They do not carry the bump stops or dust covers, both have disintegrated on mine (original from 1993). I'm going to order those, the German Porsche guy says not to replace the top mount ($$$$) but to replace the gasket between top mount and strut tower. Anyone know a part number or source for this? I'd like to get all required parts (bump stop, dust cover, gasket) from the same vendor if possible. While I'm down there, I'd also like to swap out the sway bar bushings. I fixed my power steering leaks, but things are still a bit wet so I was thinking about urethane just in case. Thoughts?

Check out the bump stops!

cheers,
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