Coilover Brands

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TomMan7531
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Coilover Brands

Post by TomMan7531 »

Hi,

So this has been brought up a couple of times but I'm after brands, after doing a bit of digging I have found systems from Spax, BC, H&R and Gaz Gold, are there any more?

The BC units are catching my eye but say they require welding, not a route I want to go down, are there any of the above or other brands that fit straight on?

The cheapest (by far) is the Spax units, they do mention that they exclude models with self leveling suspension such as my 87 635 but I suppose this is to be expected on all coilovers and most are adjustable so this isnt as much of an issue. Please correct me if wrong, new to all of this :)

Gist of it all, are there any other coilovers that people know of that dont need welding?

Thanks :)
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tschultz
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Re: Coilover Brands

Post by tschultz »

I would do spax adjustable shocks and springs but I have heard of GAZ and haven't really been interested in modifying cars to the point where it isn't reversible. I am interested in hearing what others have to say.
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Brucey
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Re: Coilover Brands

Post by Brucey »

Welding the front strut housings is essential with coilover conversions; 'tis the nature of the beast. If you don't want to be welding your strut housings then you need to buy replacement front legs and cut/weld those instead. This in turn means that you probably need to buy new ABS sensors since they often break when they are removed from their usual home. If you do both these things then you still have a conversion that is readily reversible.

The modification/welding usually comprises cutting off the spring perch and then welding on a threaded sleeve to the original strut housing, to give adjustable spring perches. In theory it ought to be possible to have a threaded sleeve with an internal shoulder that sits on top of the strut housing but I'm not sure anyone makes them like that. In any event the original spring perch has to go, it is in the way.

BTW you may or may not have worked this out yet but the front suspension on E24 is only rendered weatherproof by having boots over the front struts. Coilover conversions do not usually allow a boot between the strut and the spring (as OEM) and (for various reasons I won't bore you with) if you want a setup with anywhere near the usual suspension travel and decent ride height adjustability, it is likely that the bottom of the springs/threaded sleeves will be near or slightly below the top of the tyre. This can mean that a boot over the springs is difficult or impossible.

Another knock-on is that it may mean that the usual limiting factor for good steering with wide-ish front tyres ( being the clearance between the strut tube and the tyre) will also be compromised, if the threaded sleeve (and/or the nuts that sit on it) come low enough. You can space the front wheels out but this always makes the steering feel worse. You may be happy with compromised steering feel on one of these cars but having had it myself for a while it is 'never again' for me....

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Re: Coilover Brands

Post by ron »

Brucey wrote: If you don't want to be welding your strut housings then you need to buy replacement front legs and cut/weld those instead.
...at £900 each!!

Brucey wrote: This in turn means that you probably need to buy new ABS sensors since they often break when they are removed from their usual home.
...which are NOT available!!
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Re: Coilover Brands

Post by Brucey »

FWIW I think fitting coilovers to a road-going E24 and expecting them to be anywhere near as civilised or as practical (or as easy to fit) as a good Bilstein setup is the stuff of fantasies. But you can do it.

For strut housings, you can find used ones without too much difficulty, which will probably have rotten spring perches. No worries, these are going to be removed anyway!

For ABS sensors you can buy the E28 version and lengthen the wiring.

None of this stuff is easy. Not anywhere near as easy as fitting a set of Bilsteins is....

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Re: Coilover Brands

Post by ron »

Brucey wrote: For ABS sensors you can buy the E28 version and lengthen the wiring.
The E28 version does not fit. The probe itself is too short.
They are ALWAYS rustier than you thought!!!!!!
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Re: Coilover Brands

Post by Brucey »

ron wrote:
Brucey wrote: For ABS sensors you can buy the E28 version and lengthen the wiring.
The E28 version does not fit. The probe itself is too short.
are you quite sure? The E28 ABS sensor, when fitted to an E28, plugs into the same housing PN and reads the same hub PN as E24. They ought to be identical at the business end.

Is it perhaps possible that you have got hold of the wrong part, or that you have tried fitting it to a housing that is deformed or that still has part of an old sensor left in it or something?

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Re: Coilover Brands

Post by ron »

Brucey wrote:
...are you quite sure? The E28 ABS sensor, when fitted to an E28, plugs into the same housing PN and reads the same hub PN as E24. They ought to be identical at the business end.
I sold a local friend a pair of repaired front struts after one of his lost it's spring support cup. The spring went through the tyre! He was very lucky as he was only doing 10 mph. 10 mins later and he would have been on the motorway!

He put the car into a local BMW specialist to fit the struts. Obviously when they tried removing the ABS sensors they got mangled. Unable to find the E24 sensors (anywhere in the world) they ordered the E28 ones as they assumed that, as the struts were common to both models, they would fit.

When they came to fit them they were discovered to fit into the strut but to be too short to reach the toothed sender wheel.

They called me as, from past experience with E24s, I might have the answer.

Luckily I have a pair of E24 sensors and we checked out part numbers (both BMW and Bosch) and dimensions etc.

I have since talked to the Parts expert from the BMW Car Club who took all of the details. He was going to contact BMW and try to find out why they don't fit.

Still waiting to hear back from him but will chase him up later today and report any progress.
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Re: Coilover Brands

Post by Brucey »

Image
E28 front ABS sensor (34 52 1 154 044)

E24 front ABS sensor (34 52 1 179 981)
Image

Looks like the same sensor, different wire length, to me, which is what you would expect.

Did your 'E28 sensor' look like 044 above? If not, it probably wouldn't have worked on an E28 either...?

Did you take any pictures of the alleged E28 sensor?

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Re: Coilover Brands

Post by ron »

I didn't actually see the E28 items. I will call the garage tomorrow to see if they still have them.
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'87 M #367
'88 High line.
'10 X5
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Re: Coilover Brands

Post by TomMan7531 »

Maybe for now Ill pick up some lowering springs as thats the main reason I wanted coilovers.

Again, how will this affect the self leveling suspension?

Thanks,
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Re: Coilover Brands

Post by ron »

TomMan7531 wrote:Again, how will this affect the self leveling suspension
Are you sure you have "self-leveling suspension"? I've never seen it on a UK car.
They are ALWAYS rustier than you thought!!!!!!
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'87 M #367
'88 High line.
'10 X5
‘84 Alfasud 1.5 ti
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Re: Coilover Brands

Post by TomMan7531 »

Its got the fuse in place and the ball thing under the bonnet (PRESSURE ACCUMULATOR) which the service pulled up as leaking helium (that could be wrong though)
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Re: Coilover Brands

Post by ron »

TomMan7531 wrote: .....and the ball thing under the bonnet (PRESSURE ACCUMULATOR) which the service pulled up as leaking helium (that could be wrong though)
This has got nothing to do with "self-leveling" suspension. It has nitrogen inside NOT Helium. Suggest you change your garage!

http://www.realoem.com/bmw/enUS/showpar ... Id=34_0271

http://www.realoem.com/bmw/enUS/showpar ... Id=34_0294

You say your car is '87. What month was it manufactured? Makes a LOT of difference if it's pre. or post 6/87.
Is it a Highline or has it got chrome bumpers?
They are ALWAYS rustier than you thought!!!!!!
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'87 M #367
'88 High line.
'10 X5
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Re: Coilover Brands

Post by Brucey »

looks like a chrome bumper car in the avatar pic.

lowering springs are an easy route to go and you can always change back again if you get cheesed off with it.

BTW there are a lot of springs out there which are of poor design and/or lower the car too much. By 'too much' I mean that the camber and toe settings go to pot and this (unless corrected, typically at vast expense and complication) causes uneven tyre wear (front and rear). As a rule of thumb lowering the car to M635-esque ride height (about 3/4" below stock) causes few geometry problems but any lower than that and issues start to multiply.

By 'poor design' I mean (for example) that the front springs don't have an integer number of turns. Because the upper spring mount is stepped and inclined vs the damper shaft, a spring with (say) 5-1/2 turns will be bent like a banana when it is installed, because the top mount has to be rotated 180 degrees making the angle all wrong. TBH given the choice between springs like that and cut-down standard springs, the latter (which would normally be a lash-up) seem quite appealing...

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Re: Coilover Brands

Post by TomMan7531 »

Thanks Brucey, and yes it a 1987 non highline, first registered on 01/08/1987.

Most the brands I see for these lowering springs lower it by 35mm currently looking at a set that lower it by 30mm which are below, is that 'too low' more to the point I dont want to be grounding out :)

http://www.europerformance.co.uk/pages/ ... ar=bmw6e24

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Re: Coilover Brands

Post by Brucey »

the link is for H&R springs. Do check, but IIRC these have a non-integer number of turns at the front, i.e. they fall into the 'crap' category.

30 mm drop is in the territory where you will start to get uneven tyre wear unless you also correct camber and toe settings.

E24 has long overhangs and the UK is infested with speed bumps; look under your front spoiler and I would bet money you can see where the nose has already kissed the tarmac even at the stock ride height. Subtract 30mm and each 'kiss' can become a 'kiss of death' for the spoiler instead.

Only you can decide if the (typically degraded) ride quality, increased tyre wear and increased risk of clouting something is 'worth it' for some highly subjective difference in the look of the car....

If you want to go quickly round corners on normal (i.e. bumpy) roads there is a whole different approach to be taken, in which lowering is not a major feature.

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Re: Coilover Brands

Post by TomMan7531 »

Ok fair enough, maybe a bit low but cant find any that dont lower it by that much, any one have suggestions?
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Re: Coilover Brands

Post by Brucey »

there are very many OEM springs that fit various (lighter built) models of BMW that you can use to lower your car

viewtopic.php?f=17&t=16947

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Re: Coilover Brands

Post by jpr210 »

Don't be discouraged in your search for coilovers. Ground Control can help you our and GAZ seems to make a very finished product. The smaller diameter spring will give you the best clearance for your tires and wheels and the adjustability will allow you to tailor the handling characteristics. Every Time anyone in recent history anyone has asked about this topic, all the contributions are not about the options but on why you should not do it.
I have hand MANY bilstein sports applications in different cars from Alfa to mercedes and now on the M6 and while serviceable, they are not the last word in damping refinement or control, the KW coilovers in my 968 are far superior in ride comfort, damping, adjustability and quality to the bilstein sports they replaced; the only drawback is price. Bilstein sports are just easy to find and buy and therefore the only thing most users know. I have bought the front shock housings to send to GAZ to the the gold coilover conversion. Stay tuned.

Thanks

Jpr
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