BMW M3 Forum (E90 E92)

BMW Garage BMW Meets Register Search Today's Posts Mark Forums Read


Go Back   M3Post - BMW M3 Forum > E90/E92 M3 Technical Topics > Suspension | Brakes | Chassis
 
BPM
Post Reply
 
Thread Tools Search this Thread
      09-22-2019, 01:25 AM   #1
simpleM3
Major
simpleM3's Avatar
66
Rep
1,120
Posts

Drives: 11 | E90 | ZCP | 6MT
Join Date: Nov 2013
Location: Arlington, VA

iTrader: (12)

Sway Bar End Links on Lowered Suspension

I started thread because although this topic has been discussed, I don't think the proper context has been added to it.

Based on what I've found in my research, some people have gone with shorter adjustable end links and other have gone with longer adjustable links. Some coilover kits even come supplied with links and when they do they're typically shorter links.

The one critical piece of detail that has been left out of every thread/topic regarding end links after lowering is the question of how is the height adjusted on the coilovers..

I think the difference or determining factor on whether shorter vs longer are needed depends on whether your suspension height adjustments are spring-adjusted, e.g. KWs, or strut-adjusted, e.g., Ohlins.

If my theory is correct, spring-adjustable coils = longer links are required and strut adjustable coilovers = shorter links.

The part that is effected the most is the lower control arms. Spring adjustable coilovers don't effect the position of the control arm, at least not significantly. When adjustment are made from the spring, it's a top-to-bottom effect. Whereas, when you're making the strut shorter, it's opposite, where the bottom needs to reach the top. So when the adjustments are made to the strut, a shorter strut means the strut carrier/hub would need to be raised up in orderer the strut to properly sit in the carrier.

I could be wrong, but I'm hoping to initiate a productive conversation on the topic because I've been suffering from this problem for over a month now and would like to have it resolved before I spend anymore money trying to address it.
__________________
2011 E90 M3 ZCP 6MT | Macht Schnell | LUX H8 V5 | Ohlins | Vorshlag | Apex | AutoSolution
2006 E90 330i AT | Macht Schnell | Eibach | Bilstein B8
Appreciate 0
      09-22-2019, 06:53 AM   #2
pbonsalb
Major General
2041
Rep
6,321
Posts

Drives: 08 E90 M3, 99 E36 M3 Turbo
Join Date: Feb 2011
Location: Concord, NH

iTrader: (3)

Also depends on whether the coilover relocates the upper link mount relative to stock.
Appreciate 0
      10-08-2019, 08:21 AM   #3
954MM
奈良シカマル
954MM's Avatar
United_States
357
Rep
349
Posts

Drives: 2011 Space Gray E90 M3
Join Date: Oct 2016
Location: Broward County, FL

iTrader: (0)

So what about lowering springs?
__________________


http://954mm.com

IG: @954MM/@954M3
Appreciate 0
      10-09-2019, 10:05 PM   #4
simpleM3
Major
simpleM3's Avatar
66
Rep
1,120
Posts

Drives: 11 | E90 | ZCP | 6MT
Join Date: Nov 2013
Location: Arlington, VA

iTrader: (12)

No issues with lowering springs

Quote:
Originally Posted by 954MM View Post
So what about lowering springs?
__________________
2011 E90 M3 ZCP 6MT | Macht Schnell | LUX H8 V5 | Ohlins | Vorshlag | Apex | AutoSolution
2006 E90 330i AT | Macht Schnell | Eibach | Bilstein B8
Appreciate 0
      10-10-2019, 06:34 AM   #5
954MM
奈良シカマル
954MM's Avatar
United_States
357
Rep
349
Posts

Drives: 2011 Space Gray E90 M3
Join Date: Oct 2016
Location: Broward County, FL

iTrader: (0)

Quote:
Originally Posted by simpleM3 View Post
No issues with lowering springs
A friend of mine said I should get shorter ones. I bent one the other day (I dont know how). It's always my ride side giving me a clicking sound. This is my 2nd replacement. All bolts were torqued down.
__________________


http://954mm.com

IG: @954MM/@954M3
Appreciate 0
      10-14-2019, 02:47 PM   #6
simpleM3
Major
simpleM3's Avatar
66
Rep
1,120
Posts

Drives: 11 | E90 | ZCP | 6MT
Join Date: Nov 2013
Location: Arlington, VA

iTrader: (12)

That's interesting. I have yet to find consistent guidance on this matter.

Some say you need shorter and others say longer.

I suspect that it depends on how the car is lowered; meaning:

My unproven and unconfirmed theories are as followings. All, of which are predicated on a unknown degree of lowering that chnages the geometry of the suspension just enough to exceed the limitations of the stock end links:

1. Coilovers that are lowered by way of compressing the springs (e.g., KW)
2. Strut oriented height adjustments (e.g., Ohlins)
3. Lowering springs (e.g., H&R)

I believe longer links are required for #2 and shorter ones are required for 1&3 after a certain degree of lowering is performed. For instances, Ohlins doesn't recommend replacing stock with adjustable links as log as their recommended height adjustment isn't exceeded.

We need one of those really smart guys to chime and clear hit us with the fancy math and physics.

Quote:
Originally Posted by 954MM View Post
A friend of mine said I should get shorter ones. I bent one the other day (I dont know how). It's always my ride side giving me a clicking sound. This is my 2nd replacement. All bolts were torqued down.
__________________
2011 E90 M3 ZCP 6MT | Macht Schnell | LUX H8 V5 | Ohlins | Vorshlag | Apex | AutoSolution
2006 E90 330i AT | Macht Schnell | Eibach | Bilstein B8
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -5. The time now is 01:58 PM.




m3post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2019, vBulletin Solutions Inc.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST