Fitting Z3M top mounts to a standard Z3 (2.8)

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c_w
Joined: Thu 19 Aug, 2004 16:50
Posts: 4032

  M roadster S50

Fitting Z3M top mounts to a standard Z3 (2.8)

Post by c_w »

Has anyone done this as I'm thinking of doing it as it increases the castor angle and apparently much reduces the tramlining that the Z3 can be quite bad for.

I'm not sure if this is someon's webpage of here:

http://homepage.eircom.net/~roadster/index.htm

One thing I'm not sure about is why it says on that page to swap the mounts over and use the LHS mount on the RHS on a standard Z3? Does anyone know why this would be?

It appears that the M top mountsd are offset for more camber and to alter the camber too, but if you were to put them on the "Wrong" way wouldn't that result in positive camber?
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TonyCal
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Post by TonyCal »

Cw that is Jon's site, there is a posting on the forum somewhere he made when he did the mod. Yes he has fitted the M top mounts to his 2.8, I believe there is a section on this on an american site too but the name escapes me at the moment.
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c_w
Joined: Thu 19 Aug, 2004 16:50
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  M roadster S50

Post by c_w »

I e-mailed him and he pointed me to an American BMW BBS which has quite a lot of debate over these top mounts.

The mounts are offset for camber and for castor but fitting the mounts the "correct" way around will result in POSITIVE camber on a regular Z3 on standard suspension; this is because the struts, arms and hubs on the Z3M are different (so fitted correctly on a Z3M results in a bit of negative camber).

Fitting them the "wrong" way around on a regular Z3 results in a quite a bit of negative camber (more than the Z3M).

However if you lower a Z3 it gets negative camber anyway so I'm hoping fiiting the Z3M top mounts the correct way round will reduce the neg camber but still leave a little.
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c_w
Joined: Thu 19 Aug, 2004 16:50
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  M roadster S50

Post by c_w »

Just an update on the Z3M top mounts for anyone interested.

I ordered the Z3M top mounts (which are the same as the 96-on E36 M3) and the camber is offset on the top mount so that when fitted to a lowered Z3 they relieve some of the negative camber (like mine), but fitted to a standard Z3 they will probably introduce positive camber - which is why it is recommended to fit them to the opposite side. Though this introduces negative camber on a standard height Z3 as well as the additional castor.

However, 1995 E36 M3s use top mounts that have additional caster but no camber change so these will be suitable to a standard height Z3.

It does get rid of pretty all of the tram lining; it's now tram lines only occassionally like most cars would do with 225 section tyres. Before I found the level of tramlining dangerous on some roads. It did raise the front of mine very slightly as mentioned in the article on that website, but it was fine on mine as the lowering kit lowered the car more than I anticipated!

There is a slight penatly in the ride as the M3 top mounts have less rubber on them but it's not totally noticeable and doesn't make the ride crashy.

Strangely my scuttle shake problem was not affected by lowering the car and fitting Z3M top mounts, if anything it became less.
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Jon Miller
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Post by Jon Miller »

I have now done around 5000 miles (including the trip to the Lakes and Back) with the Z3M mounts fitted (the wrong way around) and have no adverse tyre wear so the increase in negative camber can't be to severe!

In my opinion it certainly is a better drive with them fitted.

Cheers
Jon
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c_w
Joined: Thu 19 Aug, 2004 16:50
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  M roadster S50

Post by c_w »

Hi Jon, yes, I bet it's the same as what I have now sine mine is lowered (which gave it a lot of neg camber, but reduced slightly with the Z3M mounts on "right" way). How are you finding inner arch clearance? I've noticed on mine the driver side just skims it slightly to scrap the mud off but nothing more; the passenger has that slight bit more clearance not to touch.

Just letting everyone know that the '95 M3 top mounts are only castor adjusted, I didn't know these existed until I had orderd the 96-onM3 / Z3M mounts and then started to worry about excessive neg. camber putting them the wrong way and positive or zero negativecamber on the other way. Luckily they turned out to be just right fitted the correct way.

I also ordered the Z3M top spring plates and rubbers etc but they won't fit a Z3 strut assembly as the Z3M uses a smaller spring diameter.
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Devon Z
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  Z3 roadster 2.0
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Post by Devon Z »

Hi c_w, so you only needed to fit the top mounts? and what geometry settings have you used?. I've had Eibach springs on my 2.0 since it was two months old and I had the geometry checked by the dealer who said it was spot on the schnitzer settings they used, I'm thinking of doing this mod if it will sort some more of the tram-lining(it got 50% better when i switched from original Dunlops to Pilots) i read about it some time ago on the US forum but was'nt shore how good it would be on UK roads but from what you say sounds good :D

Steve,
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c_w
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  M roadster S50

Post by c_w »

From Z3M setup the top mounts are the only compatible parts (along with the "reinforcement plates").

I think I forgot to mention that I had to cut and grind part of the spring top plate following Jon's advice on his site. This is necessary as the Z3 top plate has a kind of lip that protudes and would hit the inner arch such is the difference in castor when using Z3M top mounts. Even when this is done the struts do sit close to the back inner arches.

Using lowering springs on my standard 2.8 there was an very obvisouy increase in negative camber; I'm not sure how much camber is acceptable according BMW but it was a lot more than standard (not sure what a Z3M has but they're not as low as my Z3 is now). So fitting the Z3M mounts the correct way resulted in reduced negative camber but still some neg left.

If you camber is said to be fine then you will alter it fitting Z3M top mounts; fitted t he "right" way you will reduced negative camber, and the wrong way you will introduce a lot more negative camber. You might be better off fitting 1995 M3 top mounts as these appear to just add castor rather than altering the camber either way.

If you look at this very useful site http://www.realoem.com/bmw/select.do?vi ... g=R&arch=0 it lets you view all BMW parts and part nos. alogn with a USD price for a rough guide to the cost of parts. Just select E36 M3 1995 and search for front axle strut assembly parts.
Vanne
Joined: Sat 30 Apr, 2011 20:37
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Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Vanne »

I just did this to my car, 2002 Z3 3.0 roady.
I didn't do it for tramlining, but to be able to fit my front 18 inch (M5) style 32's. The rear was a perfect fit, but the front stuck out about 1.5cm..

I used the z3m top hats as described here in reverse, so brought on quite a bit of neg camber, but that wasn't enough to fit the wheel. So I used a camber kit from Turner's.. used 1 washer between the hub and the strut and now fits perfectly..

How much negitive camber does it have now? Nfi, but it's a bit :)
Vanne
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  Z3 coupe 2.8
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Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Vanne »

Needed to get my head out off the books today , so did a little spannering...

Image

Image

Image

Needed a camber kit also to bring the wheel inside the guard. One washer per side...

Image
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BladeRunner919
Joined: Fri 17 Feb, 2012 20:18
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Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by BladeRunner919 »

That looks a nice car - I'd very much like a set of style 32s!
Vanne
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  Z3 coupe 2.8
Location: Christchurch

Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Vanne »

Thanks, its a work in progress. :)

I've been driving it now for about a week with the new camber and hats. Drives fine. and holds the road very, very nicely.. though not a real fan of the STANCE club, though i guess peeps that see the car probably think i am. Lol. might fix that when new tires are needs and go slightly stretched. thinking 225/35 on the front and 255/40 on the rear. currently has 235/40 on front and 265/40 on the rear.
Howard Adams
Joined: Mon 10 Oct, 2016 15:39
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  Z3 roadster 3.0i

Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Howard Adams »

Hi, a couple of questions about these Z3m top mounts. Some one on this thread mentioned that it was best to use the mounts for 1995 Z3m, I didn't think the M series came out til 97/98, I might be wrong! (I normally am according to my Wife!)
Also do these M series mounts fit 2001/02 3.0i
Howard
Vanne
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  Z3 coupe 2.8
Location: Christchurch

Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Vanne »

Gday Howard,

As far as I know all the z3m top hats are the same part number, so no dramas which ones you will get. They are different left and right though. Mine is a 2002 3.0, so yeah no issues there.
Richardbmw
Joined: Sun 06 Jun, 2021 00:20
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  Z3 roadster 2.8

Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Richardbmw »

Hi, Just to know if someone has picture of the part need to be cut to fit the M hats. Thanks in advance.
Joycey
Joined: Mon 11 Jul, 2011 22:15
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  M roadster S52
Location: Basingstoke

Re: Fitting Z3M top mounts to a standard Z3 (2.8)

Post by Joycey »

I tried this once with standard Z3 shocks and they clash on the turret tunnel when you turn more than half the rack, wouldn't be an issue if you had coilovers. I'm sure i have photos kicking around. This is not an issues with the Z3M due to the wishbones being slightly longer and spring top being narrower.
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