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Hello all,

Noob question. Have some Bilstein height adjustable circlip shock absorbers fitted in my car. At the time of fitting, i set the circlip at preferred height and tightened the tophat to create some pre-load on the spring.

Wanted to lower the car a bit more and hence adjusted the circlip a notch down. Upon doing so, I noticed that my spring was now fully extended with no preload when car was still jacked up. ie. the spring could move up/down the shock and turn.

Obviously with the car off the jack, the spring is compressed under the weight of the car.

I just wanted to know, should I pull out the shock and screw down the top hat (im assuming to the bottom of the thread to achieve any preload on the spring (if possible?)

Or is it okay to have the spring fully extended and able to move around when car is jacked up? Should the spring always be under some load regardless if on the car?

Would like to know whether I need to pull out the shocks or just adjust the circlip height regardles of any preload on the spring.

Thank you!

unfortunately life is not that simple.

top nut first....you should always do it up tight. while a side effect may have been preloading the spring in your case, it's job is to hold the shock assembly together.

re spring height and being captive....if the spring is too short to remain captive, you can either ignore it and live with the knocking noise (lots of race cars do but I think it's too annoying in a road car), or get helper springs. The helper spring is a very light spring that stops the main spring rattling.

pat's car aint that low roy... :ermm:

its 320 on the front :ermm: and 340 on the rear. Want to lower the rear down, but when adjusting circlip it made the spring captive!

Ill pull out the shock and tighten the tophat further down! Thanks for the help

I had the bilstein's in the rear of my car before i got coilovers. I had the same problem the spring was too short so i zip tied the rear of the spring to the "seat" of the shock, just incase i went over a bump and the spring came out of its seat.

I know its not safe and a zip tie wouldnt do much but it might help if the spring was to jump out over a bump!

hahah i see....can't exactly be surprised if something isn't right at the hight :P have you calculated the roll centre and roll couple?

you referring to 320mm height for track days? I'll be adjusting back to 340-350mm for trackdays which seems to be the best height for r32's in terms of handling.

If i drop a circlip height and retighten the hat to take up some pre-load and then decide to flick the circlip back up (without re-adjusting the top hat) would this be causing any harm?

Im assuming the spring will be under more pre-load as the distance between spring seat and tophat has reduced. Would I need to unwind the tophat? How much load should be forced onto the spring?

Cheers for help again.

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