Bilstein HD + H&R 35mm Lowering Spring?

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Viktor D.
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Bilstein HD + H&R 35mm Lowering Spring?

Post by Viktor D. »

Just a quick question:

I already bought a set of Bilsteins and a set of H&R 35mm Lowering Springs, plus the 635 dampers for the top of the shock.

I understand i have the Bilstein HD's as there are only three slots for the circlip on the rear shocks.

I Read that H&R Lowering Springs should be combined with Bilstein Sport shocks, and with the M635 dampers.
The problem is that I only found out after I already ordered and received my parts.

Will this give problems as I do not have the Bilstein Sport shocks in the rear?
Do I need to look for a set of Bilstein sports in the rear, or the M635 dampers or can I just run the HDs without any issues?

Kind Regards,
Viktor
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by GRNSHRK »

Viktor, the main issue is that the HD strut bodies (tubes) are longer and therefore the springs may unseat when jacking up the rear end [-X

HD and Sport struts are valved the same otherwise, they are just different lengths and that's why you "should" use Sports with lowering springs [-o<

HTH 8)
:mrgreen:
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Viktor D.
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by Viktor D. »

That's what I was afraid for.

I saw that the HD's are the same length as the original Monroe shocks that I have.
However, the H&R springs are shorter than the original springs and are no longer compressed or very very little compressed when the bilstein HDs are fully extended.
That's what makes them unseat.

As the HDs are valved the same as the Sport shocks, I guess I will use the HD's and pay attention to the springs not unseating themselves when I jack up the rear.


Except if someone would have bad experiences with the springs unseating themselves quite often, even while driving?
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Viktor
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by GRNSHRK »

Viktor, not likely to happen whilst driving, unless you go airborne \:D/

And since it's not like you're jacking up the rear end of your 6er every other day, and as long as you ensure that the springs seat properly when lowering off the jack, you "should" be OK [-o<

As I had a mismatched setup on my 6er as purchased, I didn't realize what the problem was for quite a while :shock:

What happened was damage to the spring cups on the topside mounts, which would get bent if the spring caught it wrong when being lowered off the jack, which caused a nasty squeaking sound [-X

And THAT'S when I realized that something is amiss ](*,)

Once again, HTH :-({|=
:mrgreen:
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Viktor D.
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by Viktor D. »

Ok, Thanks for the help and the quick replies Bobbo! =D>

Now that I know this can occur, I'll pay extra attention to it when lowering the jack!

Getting airborne is not something I plan on doing, but you never know :lol:
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by hornhospital »

I don't know for sure about the E24 mismatch, but on an E36, if you run lowering springs with stock height shocks/struts, it beats the struts/shocks to death because they are constantly bottoming out. Been there.....
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by madridcab »

I am running Bilstein B6 with H&R springs on one of my sixes, and Bilstein B8 with same H&R springs on the other. Have not had any problems with either. Although they should be same valving etc., the one with B6s has a significantly smoother ride for some reason.
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by wattsmonkey »

Horses for courses, but I took the H&Rs off my six pretty damn sharpish. As above, unless you get airborne they aren't going to unseat themselves on the road, but they'll do so when you jack the rear end up.

If you look at Realoem you'll see the difference in length between the standard bumpstops and those for the M635. I'd imagine the rear shocks will be riding on the bumpstops pretty much all of the time if you use the standard ones with lower springs.

The six does look cool with the drop though!

Cheers,

Rob
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Re: Bilstein HD + H&R 35mm Lowering Spring?

Post by Brucey »

IIRC the HDs use the same damper body (tube) length as the sport shocks. The difference in the overall shock length comes from a difference in the damper rod length.

If you want to fix the problem you have (dislocation) then you can perhaps fit 'helper springs' which are compressed flat most of the time, but extend when the car is jacked up to prevent the springs from rattling on full droop. Obviously this will require a perch height adjustment. Helper springs are not available in all diameters.

In the long term a shock rebuilder (if you ever have the shocks rebuilt) can modify the damper rods (which might not require the shocks to be stripped), or fit shorter damper rods or put spacers inside your shocks which will restrict the shock travel by limiting how much of the damper rod ever pokes out of the top of the shock.

I believe there are also progressively wound springs which lower the car whilst allowing the use of full-length shocks with full negative travel.

As per the above post I think you will want to have the shorter bumpstops fitted (and BTW 'no bumpstops' would be a dumb choice IMHO).

cheers
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