ebay camber top mounts, do they work?

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kembrey
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Post Sat Jun 16, 2012 6:50 pm

hi there im new to this forum and a new e30 owner, im a drifter and would like to know if the ebay camber adjusters where they sit on the rear top mount and adjust as you tighten the shock, to me it seems that it wouldnt work.
any help would be much appreciated !
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Post Sat Jun 16, 2012 7:27 pm

link?
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

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http://www.e30zone.net/modules.php?name ... =viewtopic&
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Brianmoooore
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Post Sat Jun 16, 2012 9:29 pm

Damper top mounts at the front of the car can be used to adjust camber, but the rear top mounts simply hold the top of the damper in place, and can't possibly affect suspension geometry.
Alterations at the back end are usually done via slotted mounting plates welded to the rear beam, and eccentric bolts from a five series.
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harry_p
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Post Sat Jun 16, 2012 10:55 pm

As above, you can't adjust the rear camber with the topmount, the hub and arm are one piece so the motion of the rear wheel is controlled totally by the pivot points on the rear subframe.

Offset rear topmounts are usually to give more clearance to the inner arch when using a coilover setup.
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harry
mrLEE30
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Post Sun Jun 17, 2012 9:57 am

Surely you can "adjust" the rear camber by altering the ride height, lowering adds camber due to the movement of the trailing arm. Not an elegant way but it does work.

Discuss!!
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Brianmoooore
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Post Sun Jun 17, 2012 2:37 pm

The geometry of the suspension changes toe and camber with ride height, but again, this is nothing to do with the dampers or their top mounts, other than the damper can set the limits of suspension travel.
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Post Sun Jun 17, 2012 6:21 pm

^^agree but the OP presumably wants to adjust/change the rear camber, i was just pointing out that altering the rear ride height does achieve that - although its not the most elegant of solutions.
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kembrey
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Post Sun Jun 17, 2012 11:11 pm

http://www.ebay.co.uk/itm/BMW-Rear-Camb ... 702wt_1172

those and, how adjustable can the welded of brackets be?
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Post Mon Jun 18, 2012 6:11 am

they are not camber adjusting mounts but they do look like passable cheep heavy duty top mounts.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822

m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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kembrey
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Post Mon Jun 18, 2012 10:14 am

so essentially they will do nothing ?
mrLEE30
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Post Mon Jun 18, 2012 12:31 pm

kembrey wrote:so essentially they will do nothing ?
like Brian says above you cannot adjust the rear camber by the top mounts, the camber is fixed by the two mounting points of the trailing arm to the sub frame. as the trailing arm travels upwards it naturally adds camber due to the angle of the mounts, so if you lower the car this also naturally adds camber upto about 3-4 degrees on full travel.

the other way is to make the bushes or the tabs eccentric that hold the traling arm to the sub frame. this then gives you some adjustment of the angle of the trailing arms and thus the camber.

fronts can be fully adjusted by adding adjustable top mounts.

out of interest do you understand the relationship of camber/grip/handling/suspension set up? if you do not understand the basic principles of the suspension system it may not be the best idea to throw money at trying to alter the rear camber. best to fit decent suspension first, if you have not already done so. rear grip will be more affected by changing of the rear antiroll bar stiffness/spring rate/damping rather than camber.

adjustable ARM mounts and coil overs will allow these adjustments, with the added bonus of adjustable fronts to alter front end grip (if you race carts you will know that the search for rear end grip/slide is possible by gaining or loosing grip at the front.
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kembrey
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Post Tue Jun 19, 2012 4:47 pm

ahh right sweet!, and i was mainly only going to buy them to adjust the camber for shows etc, to allow for arch clearance, im happy with the position of it at the moment, but if i go any lower i feel it may hit the arches, as for the front i will defiantly be investing in camber adjustable mounts for more camber, as for grip, im not too fussed as the cars used for drifting and im happy with the amount its got at the moment.
cheers for all the help!