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Spax lowering kit

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rrrs
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Spax lowering kit

Post by rrrs » Tue Jul 28, 2020 4:28 am

Hi, is there someone with experience on Spax lowering kit

https://www.demon-tweeks.com/us/spax-ps ... spxtap099/

It is much better priced than typical B9/HnR kit; about $300 less including shipping and it offers adjustable damper.
I seen many very favorable reviews on Spax springs in E28 forums, but most of them seem to be used with B9 shocks; not much feedback on Spax shocks.

I realize they are quite low (35mm lowering) which might be good considering I would like to add IE upper camber plates which should add back about 5mm of height.

Is there option to adjust the rear height on Spax setup; something like on Bielstein where one can move the spring seat height?

Anything else to consider/be aware of before deciding for this?

rrrs
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Re: Spax lowering kit

Post by rrrs » Tue Jul 28, 2020 11:22 pm

So, seems not many have this kit installed; I think I will go ahead and post back the report....but it will take some months before they will be on the car.
Thinking to pair them with IE sway bar kit https://www.iemotorsport.com/product/sw ... r-e24-e28/
And their fixed upper camber plates.

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Re: Spax lowering kit

Post by jps635 » Wed Jul 29, 2020 6:56 am

Type spax into the search box at the top. Haven't read them but a number of posts.
'85 635csi JPS (RA2-66)

rrrs
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Re: Spax lowering kit

Post by rrrs » Thu Jul 30, 2020 7:46 am

Thanks for the tip, I actually did this first and although there come number of post there is no report from someone that has the whole kit (springs and shocks)'
Much more useful info I did find on E28 forum with lots of very positive posts, but I am not sure if E28 setup would translate directly to E24.
I will go ahead and report how I like them once I get them installed.

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Re: Spax lowering kit

Post by bpoliakoff » Thu Jul 30, 2020 7:01 pm

Which chassis do you have? E28 suspension will not cross over to an E12 suspension(pre82) and the drop is 1.35 Most lowering springs offered usually state a drop of 1.25-1.35 as they allow themselves some wiggle room based on weight etc Plus what they are showing in the link you provided states it will not fit a pre 82 car

If interested I have a set of proper ST springs and an adjustable 24mm rear sway bar
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.

rrrs
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Re: Spax lowering kit

Post by rrrs » Fri Jul 31, 2020 10:24 pm

Hi, it is '85 car, so yes, 28 based.
I already ordered the Spax lowering kit that includes springs and shocks, but am still looking for a swaybar setup.

Based on reading some posts on this forum, seems that preferred setup is 22mm front (ST makes this) combined with 18mm rear (from E28 M5).
Other option that seem to work well from the feedback is 25mm front and 19 rear (I think this is no longer available ST setup).

Please let me know what swaybars you got, would be very interested if they suit.
I guess you meant 24mm front, not the rear?

Since my front will be a bit heavier than standard (it is getting turbo-setup from 745i) thicker bar could be good.
I realize it will require new mounts, but that should be OK to get weld-in.

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Re: Spax lowering kit

Post by bpoliakoff » Sat Aug 01, 2020 1:23 am

My 81 Euro has a 25mm front stock from factory 18mm rear
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.

rrrs
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Re: Spax lowering kit

Post by rrrs » Sat Aug 22, 2020 6:39 am

My Spax kit arrived; looks like a really nice quality, adjustable shocks front and rear.

Hoping to install over the weekend, but just wondering about two points, if someone could help:

1) I got new bump stops; the kit does not include the bump stops with it. Should I use the OEM once and should I use them as they are or cut them shorter?

2) I read that one should fill the strut housing with oil, but not to do it with Bielsteins. Should I use any oil or grease when inserting front struts in the housings?

Thanks a lot, will post the pictures once done!

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hornhospital
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Re: Spax lowering kit

Post by hornhospital » Sat Aug 22, 2020 6:44 am

If they're stock length bump stops you'll need to shorten them by the amount of drop from stock.

I don't know about the oil. I believe it was intended to help cool the shocks, but I'd never heard you don't add oil with Bilsteins.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann";'87 325is "Odette"; '93 325is "Elvira"; '95 M3 "Ashlyn"; '95 318is "Bebe"

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Re: Spax lowering kit

Post by bpoliakoff » Sat Aug 22, 2020 5:53 pm

The Bils fit slip fit tight in the strut housings so if any oil, it will be minimal
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.

rrrs
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Re: Spax lowering kit

Post by rrrs » Mon Aug 24, 2020 9:54 pm

Hi, thanks for the feedback; got all front components off and am going to re-fresh (clean and paint) the strut housings while they are off the car.

I am still wondering about the oil and if I should use it or not; in my Bentley E28 manual stands : "if using gas filled strut inserts do NOT use the oil in the strut housings"; Spax are Krypton gas filled, so I guess that would mean no oil.....probably best to leave them without oil and maybe just spray some white lithium grease inside as the future rust prevention?

Regarding the bump stops, on Spax page I found following:
"What should I do with my original bump stops when I fit lowered springs?
You should always keep the original bump stops. If they are not in good condition, replace them."

I guess this would mean that I should not shorten them?
Problem I see with shortening bum stops is that if I cut the bottom off then I loose the dust protector locating groove and if I cut the top then the narrow ID part that keeps them in place is lost?

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Re: Spax lowering kit

Post by jps635 » Tue Aug 25, 2020 6:56 am

'85 635csi JPS (RA2-66)

rrrs
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Re: Spax lowering kit

Post by rrrs » Wed Aug 26, 2020 1:47 am

OK, thanks, so will go ahead and trim the top of the bump stops by one groove (this makes it about 35mm shorter, so should match Spax sprigs).
To hold them on the top of the strut insert rod probably my best bet will be just a very small amount of gorilla glue, since the narrower part of the bump stop that holds it in place will have to get cut off.
Will dispose the oil from the strut housings, as Bruce suggested.

rrrs
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Re: Spax lowering kit

Post by rrrs » Mon Sep 07, 2020 4:27 am

Hi, I am still in process of suspension rebuild; it is taking longer than expected since I am trying to clean and repaint most of the components....

I am also using Meyle HD rear sub frame mount bushing but fill them with liquid Polyurethane, 80 hardness before installing.

I also wanted to do the same with front upper control arm (trust arm) bushing, to tape it off and fill with Polyurethane, but I am worried if this could create a problems there.
I fail to understand how is this arm articulating in up-down direction as it seems that it is not designed to rotate around the large mounting bolt; is it the give/flex in the rubber of the bushing that is critical to let this move up and down as suspension travels?
This would mean that filling the large voids in this bushing could really cause problems and maybe even break something?

I realize they sell Poly bushings for this location, but they make them totally without rubber and are probably made to rotate around the polyurethane insert; rubber ones are not made to rotate but just flex within the bushing, if I understand correct?

I will eventually get the mossehead ones in the future, but at the moment they are not available and would like to experiment with poly filled rubber bushings, as long as this is something that could be OK to try and not cause other problems?

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Re: Spax lowering kit

Post by 86_6series » Mon Sep 07, 2020 12:27 pm

Don't forget to pre-load before torquing.

rrrs
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Re: Spax lowering kit

Post by rrrs » Tue Sep 08, 2020 6:51 am

Thanks for reminder, will definitely make sure to pre-load the suspension before tightening control arms.
Finished pouring the 2-part Urethane into the bushings and they came out really nice; now hope the extra stiffness this ads to normally very open bushings will not cause some unexpected problems...

Here are couple of photos of both, Rear sub frame and trust arm bushings filled with 80 hardness polyurethane.

I poured the urethane to be flush with arm mount so it should be held in place/squeezed with the trust arm bracket.
IMG_0423.jpg
IMG_0423.jpg (127.72 KiB) Viewed 113 times
IMG_0424.jpg
IMG_0424.jpg (142.56 KiB) Viewed 113 times

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