Rear shocks…., Sorry if covered 100’s of times Options

[Freezin 914]

Recently assembled new rear shocks, Bilsteins.

100# springs, new rubber parts, stock and new lower perches.

I assembled them without springs compressed, and tightened the factory nut assembly (#10 PET) until tight. I believe it is threaded on all the way. Then temporarily slid new rubber bits over the top……my questions are:

My donor shocks had some plastic washers under the hats, do I reuse them?

Do I need any jounce rubber pieces? (Have never seen them used on any of the cars I have parted, or worked on)

Last question, the new nylock nut doesn’t look like it will catch the nylon? Should I use the top nuts I removed from old shocks? I assume the nylon lock nuts would be preferred.

[bkrantz]

Off the top of my head, I think the Bilsteins have inner bounce stops.

[Superhawk996]

Off the top of my head, I think the Bilsteins have inner bounce stops.

Bilstein yellow sport rear dampers are a monotube design and the “jounce bumper” is inside the tube. [edit: this pertains to the front strut cartridge only]

Monotube dampers are a little bit different because they have a floating gas piston inside the damper body that contains the high pressure gas.

I could be mistaken but I believe the rear dampers don’t have a conventional rubber jounce bumper inside but when the piston and oil flow nears full compression travel, the pressure in the floating piston getting compressed further and further acts like jounce bumper as its gas pressure increases - preventing a hard crash of the piston into damper tube at its end of travel. edit

(Edit addition). I’m now confused myself. I went digging in the Bilstein catalog for p/n 24-001793 to get you a solid reference and it references an internal rebound stop but says nothing about a jounce bumper stop. I can tell you when I assembled mine I didn’t use an external jounce bumper but now I’m doubting myself (IMG:style_emoticons/default/unsure.gif)

Install instructions don’t clarify.

I may have to contact Bilstein to see what they say.

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[StarBear]

Just did mine, the same configuration. No, the jounce bumpers aren’t needed, nor the two each side additional rubber rings. Same questions also so took a few days as yes the instructions aren’t clear. They seem to be used on just Boge struts.
Also not clear on the bottom movable rings and orientation of the bottom plate ( lip down).
Be sure to do alignment as change will alter stuff - in my case quite a bit! Nose may be up after springs settle so adjust torsion bar screw.
Ian Karr has a video on the basics.

[Superhawk996]

@freezin 914

[L-Jet914]

When I replaced my rear shocks with the same Bilsteins, I reused the bump stops and all the hardware etc that were on my old rear shocks. I also installed new rubber isolators in their respective locations. I also placed the circlip on the 5th from the bottom after I inquired about spring perch height to a factory rear shock absorber.