E90Post
 


 
BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > Suspension | Brakes | Chassis > Sway and roll bars and braces - how should I tighten up my suspension?



Reply
 
Thread Tools Search this Thread
      10-31-2018, 04:09 PM   #1
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Sway and roll bars and braces - how should I tighten up my suspension?

I'm looking to tighten up my suspension, specifically body roll and rear step-out. Step up and make a suggestion!

Here's what I'm running right now on a 2009 335i with Sport package:

ST V1 coilovers
BC Forged 18x10 and 18x11 wheels with Pilot Super Sports (biggest I could fit)
M3 suspension: 11pc FCP Euro upgrade kit

I don't want the car to be any more harsh, I'm looking to reduce roll and provide a nice, predictable step-out characteristic in the rear. And yes, an LSD is on the list soon enough.

How should I change my anti-sway and anti-roll bars? Should I upgrade the strut tower brace in front? Rear (if there even is one stock)?
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      10-31-2018, 04:57 PM   #2
cvc 22349a
Colonel
cvc 22349a's Avatar
United_States
164
Rep
2,556
Posts

Drives: 335i
Join Date: Sep 2007
Location: SF Bay

iTrader: (11)

M3 or firmer rear subframe bushings, Megan racing rear toe arms, firmer differential bushings will tighten up the rear end.
For body roll you can lower your car, get a quality coilover suspension or larger sway bars, M3 or Dinan.
Strut tower brace is useless unless it's a track car.
__________________
2007 E90 335i, TiAg, 6AT, ZPP, ZSP, ZCW, 6FL, HD
Quaife lsd, ETS fmic, GIAC s/w, Dinan intake/exhaust/oc, Koni/M3 susp, Apex Arc 8, Mich PSS
Appreciate 0
      10-31-2018, 05:07 PM   #3
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by cvc 22349a View Post
M3 or firmer rear subframe bushings, Megan racing rear toe arms, firmer differential bushings will tighten up the rear end.
For body roll you can lower your car, get a quality coilover suspension or larger sway bars, M3 or Dinan.
Strut tower brace is useless unless it's a track car.
As you'll note, I already have quality coilovers. ST V1s are the same as the KW V1s, just galvanized steel instead of stainless, and it's already lowered.

I'm not interested in a harsher suspension, so I'm trying to avoid the subframe bushings. Forgive my ignorance, but what do rear toe control arms do for me?

For sways, what do you think about the H&R kits (27mm front 20mm rear (Search "Sku # : HR_Swaybars_E90_PR" since I'm pretty sure I can't link to m o d b a r g a i n s)) vs the Hotchkiss (https://www.turnermotorsport.com/p-5...way-bar-kit/)?
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      10-31-2018, 05:48 PM   #4
cvc 22349a
Colonel
cvc 22349a's Avatar
United_States
164
Rep
2,556
Posts

Drives: 335i
Join Date: Sep 2007
Location: SF Bay

iTrader: (11)

You mentioned rear step out. If you want to reduce rear end side to side slop the rear subframe bushings are the primary culprit along with the toe arms.
I don't have experience with those sway bars and think they're too stiff.
Yes I saw you have V1's I had KW's once too.
__________________
2007 E90 335i, TiAg, 6AT, ZPP, ZSP, ZCW, 6FL, HD
Quaife lsd, ETS fmic, GIAC s/w, Dinan intake/exhaust/oc, Koni/M3 susp, Apex Arc 8, Mich PSS
Appreciate 0
      10-31-2018, 05:54 PM   #5
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by cvc 22349a View Post
You mentioned rear step out. If you want to reduce rear end side to side slop the rear subframe bushings are the primary culprit along with the toe arms.
I don't have experience with those sway bars and think they're too stiff.
Yes I saw you have V1's I had KW's once too.
Yeah, they're not Tein Electronically Controlled, but the work well enough.

And ah, thank you. My understanding of suspension is fairly basic, and I'm trying to learn more.

I did some reading and found that the Eibach set is more street oriented (Part number 2085.320). What do you think?
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      10-31-2018, 06:43 PM   #6
cvc 22349a
Colonel
cvc 22349a's Avatar
United_States
164
Rep
2,556
Posts

Drives: 335i
Join Date: Sep 2007
Location: SF Bay

iTrader: (11)

The Eibach kit looks better kind of like Dinan. I have a BMW PS front sway bar and 14mm rear sway bar. Sway bars are the last thing you should address but make sense since you have a lot of tire.

If you want an understanding of our suspensions go back to 2007, 2008 and check out rear subframe and control arms by 'Orb' and HP Autosport. M3 rear subframe bushings or inserts won't hurt your ride quality, they will improve it along with reducing rear end slop. It is the best modification for these cars that aren't running runflat tires. If you replace the bushings with harder rubber, poly or solid mounts that's the time to replace the rear sway bar.
__________________
2007 E90 335i, TiAg, 6AT, ZPP, ZSP, ZCW, 6FL, HD
Quaife lsd, ETS fmic, GIAC s/w, Dinan intake/exhaust/oc, Koni/M3 susp, Apex Arc 8, Mich PSS
Appreciate 1
Jklad422.00
      11-01-2018, 11:50 AM   #7
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

I found a set of Eibachs new-in-box that I'm buying, but it'll be a while before I install them due to needing to drop the rear subframe. I'll probably wait until I pick up an LSD (April-ish) and do it then.

I'll look into the bushings. Thanks a bunch for your help (and enjoy some fresh Blue Bottle for me, I love the Bay)!
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      11-05-2018, 07:50 PM   #8
joeybutts
Private First Class
8
Rep
167
Posts

Drives: A dream
Join Date: Sep 2015
Location: Hampton, VA

iTrader: (0)

Sorry to hijack/deviate, could you post a picture of your vehicle with the BCForged's and post your specs? Highly interested in getting a set myself.

Thanks!
Appreciate 0
      11-06-2018, 08:12 AM   #9
FCobra94
Guest
0
Rep
n/a
Posts

Drives:


Until you get the rear bar/LSD installed, put the front one on...it only takes like ~30 minutes from start to finish and makes a big enough difference on it's own to make it worth while.

What tire sizes are you running? To get the car more neutral go with a squared wheel/tire setup next time instead of staggered.
Appreciate 0
      11-12-2018, 10:36 AM   #10
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by joeybutts View Post
Sorry to hijack/deviate, could you post a picture of your vehicle with the BCForged's and post your specs? Highly interested in getting a set myself.

Thanks!
Forgive the height; the wheels are wide enough that I need to roll the rear fenders and cut the fronts before I can drop it back down. These are Matte Bronze RZ05s.



Matte Bronze RZ05 wrapped in Pilot Super Sports
18x9et30 front 245/40/18 with a touch of camber
18x10et35 rear 275/35/18 no camber with fender roll

I was very, very specific that I did not want to run stretched tires at all.
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      11-12-2018, 10:36 AM   #11
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by FCobra94 View Post
Until you get the rear bar/LSD installed, put the front one on...it only takes like ~30 minutes from start to finish and makes a big enough difference on it's own to make it worth while.

What tire sizes are you running? To get the car more neutral go with a squared wheel/tire setup next time instead of staggered.
Given the cost of the wheels ($2800 a set), that's not very likely at this point. Tire sizes in post above.
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      11-13-2018, 12:49 AM   #12
hellokitty
Brigadier General
hellokitty's Avatar
United_States
2949
Rep
3,734
Posts

Drives: '17 M3 ZCP DCT
Join Date: Jul 2010
Location: Southern California

iTrader: (2)

I have solid aluminum rear subframe bushings, 11 piece m3 front and rear arms, manzo toe links and eibach front and rear sway bars going in this week. Will post results once I get the car back and aligned
Appreciate 1
Team503129.50
      11-13-2018, 02:21 PM   #13
joeybutts
Private First Class
8
Rep
167
Posts

Drives: A dream
Join Date: Sep 2015
Location: Hampton, VA

iTrader: (0)

Beautiful and thanks for sharing!
Appreciate 1
Team503129.50
      11-13-2018, 05:12 PM   #14
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by hellokitty View Post
I have solid aluminum rear subframe bushings, 11 piece m3 front and rear arms, manzo toe links and eibach front and rear sway bars going in this week. Will post results once I get the car back and aligned
Looking forward to it! That's the same setup I have except the bushings and toe links.
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      11-13-2018, 05:13 PM   #15
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by joeybutts View Post
Beautiful and thanks for sharing!
Thanks man, I appreciate it!
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      11-14-2018, 10:45 AM   #16
Team503
Nerd
Ireland
130
Rep
437
Posts

Drives: 2009 335i Sport/Auto/Luxury
Join Date: Jul 2013
Location: Dublin

iTrader: (5)

Quote:
Originally Posted by FCobra94 View Post
Until you get the rear bar/LSD installed, put the front one on...it only takes like ~30 minutes from start to finish and makes a big enough difference on it's own to make it worth while.

What tire sizes are you running? To get the car more neutral go with a squared wheel/tire setup next time instead of staggered.
I thought installing one without the other upset the balance of the car, exaggerating the rear sloppiness?
__________________
2009 E92 335i Sport 6AT - Finished, sold
Transport for Ireland - LEAP Pass with TFI smartapp because cars are stupid expensive in Ireland
Appreciate 0
      11-14-2018, 10:50 AM   #17
FCobra94
Guest
0
Rep
n/a
Posts

Drives:


No
Appreciate 0
      11-14-2018, 12:05 PM   #18
avocet
Major
273
Rep
1,166
Posts

Drives: 2007 328i 2011 X5d
Join Date: Sep 2010
Location: Vancouver bc

iTrader: (0)

Quote:
Originally Posted by cvc 22349a View Post
M3 or firmer rear subframe bushings, Megan racing rear toe arms, firmer differential bushings will tighten up the rear end.
For body roll you can lower your car, get a quality coilover suspension or larger sway bars, M3 or Dinan.
Strut tower brace is useless unless it's a track car.
Pretty much this. I would also suggest shock mounts if your shocks use oe style rubber.

I found a front strut bar incrementally useful, although I HPDE and track my car 5-6 times a year.

The stock SF bushings are literally crap. M3 bushings will make no perceivable difference in NVH.
Appreciate 0
      11-14-2018, 10:50 PM   #19
Jklad
Lieutenant Colonel
Jklad's Avatar
United_States
422
Rep
1,643
Posts

Drives: 2007 335i Coupe
Join Date: Nov 2010
Location: Palatine, IL

iTrader: (0)

Quote:
Originally Posted by hellokitty View Post
I have solid aluminum rear subframe bushings, 11 piece m3 front and rear arms, manzo toe links and eibach front and rear sway bars going in this week. Will post results once I get the car back and aligned
Please share some feedback on those solid rear bushings!
__________________
2007 E92 335i MT
Appreciate 0
      11-15-2018, 10:37 AM   #20
Nastymateo
Enlisted Member
Nastymateo's Avatar
33
Rep
48
Posts

Drives: 2008 BMW 335i
Join Date: Jul 2016
Location: USA CA

iTrader: (0)

Garage List
2008 BMW 335i  [0.00]
2008 BMW 335i  [0.00]
This is what I just installed. M3 subframe bushings, trw 11 piece m3 arms, Megan racing toe arms. M3 diff bushings and some st xta coil overs. Talk about a big improvement. When I launch now the car goes straight. The ride is getting better everyday. Will do a full review after a month. I want the car to settle 1st. It took me 2 days to install everything. $3k in parts. But I'm truly happy.
Attached Images
 
Appreciate 0
Reply

Bookmarks


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 12:47 AM.




e90post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, 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