BMW 3-Series (E90 E92) Forum > E90 / E92 / E93 3-series Technical Forums > Suspension | Brakes | Chassis > My Experiences with M3 Rear Subframe Bushings and Swaybar

Thread Tools Search this Thread
      05-13-2010, 10:54 PM   #1
Drives: 4 Door Family Sedan
Join Date: Sep 2009
Location: Minneapolis

Posts: 2,429
iTrader: (7)

My Experiences with M3 Rear Subframe Bushings and Swaybar

Hi All,

I figured I'd share my experiences with my newly installed M3 rear subframe bushings and swaybar.

HP Autowerks was great to deal with to supply everything, and Harold even answered when I had a question about using a shouldered bolt instead of OEMs.

Onto the install:

I made my own puller system to get the OEM bushings out and M3 ones in using 4" steel tubing and 5/8" Grade 8 bolts ranging from 8" to 3". It worked well to get the OEM ones out...but pressing the new ones in proved to require too much force for my puller, and I snapped 4 grade 8 bolts by the time I got the first one 1/2 way in. Lesson learned: You NEED a press! So I brought the subframe into my university's machine shop and used a big ol' press and they slid in like butter. For the front bushings with the square alignment dowel/pin thing, I perfected them with a 1" square rod.

The swaybar was as simple as loosening 6 bolts, slap on slap off. Granted, the entire subframe was out of the car and easy to work with.

Overall, this install was much much much easier than I expected. It's just using large tools to work with large parts and pieces. The only 'difficult' part was plugging the mid-brake lines. With the right tools, It can be done in anyone's garage without a lift.

Driving impressions:

Bushings: I was surprised how much I noticed these...especially when launching/shifting hard, you really feel the power without the absorption of the OEM bushings. Way more precise and less floaty. As for stiffness/roughness...I would compare it to changing the front OEM strut (rubbery) plate with Vorshlag camber plates...or going from 18" Non-RFTs to 19" RFTs. You feel and hear more of the road's imperfections, but I don't think it's much rougher. I would definitely recommend thesse to people who don't care if their car doesnt ride like a Cadillac and preferrs a more aggressive setup.

Swaybar: Wow again..... but in a different way. I thought the M3 rear swaybar was supposed to be the happy medium of stiffness, but in my opinion, it is too stiff for those of us without a LSD. Rallying around tight corners is guaranteed to be a one-wheeled-wonder.

All in all, It was a tough day installing..but definitely without too much of a headache.
BrianMN is offline  
Reply With Quote
      05-14-2010, 01:27 AM   #2
Enlisted Member
Drives: 07 e92 335i
Join Date: Oct 2005
Location: usa

Posts: 32
iTrader: (0)

After reading lots of posts on BMW performance suspension and M3 control arm/tension strut, sway bar,subframe bushing I still don't know which parts I need for daily driver. Because if I go for all of these, it's lots of money. So any advice on this, such as only performance suspension, or sway bar and control arm, etc.?
alam is offline  
Reply With Quote
      05-14-2010, 03:45 AM   #3
Lieutenant Colonel
Autobahn335i's Avatar
Drives: E92 335i
Join Date: Mar 2009
Location: Luxembourg

Posts: 1,599
iTrader: (5)

I can second the impressions on the subframe bushings. I had them installed together with the LSD. The M3 bushings definitely tighten up the rear end, making it more precise and less floaty.
But since I'm on 19" RFTs, it's a bit on the limit in terms of stiffness. You'll notice road imperfections ALOT more. Of course this is a subjective appreciation, but I really look forward the get the Bilstein PSS10 coilovers installed which should improve the handling and the ride quality as well.

Given the rather high shop cost to install the bushings, it's best to get this done together with other parts, such as an LSD or the rear sway bar. This allows to save on labour costs.

On a daily driver, I would suggest to get a suspension first (a good set of coilovers offers the best all-in-one package IMO). After that I would look into the front M3 conversion to get rid of understeer some more. The need for further enhancement depends on the use (tracking?) and your general expectations in the handling of the car (sports car like/good handling but more comfort oriented).
Performance Seats, Exhaust, Splitters, Pedals, Steering Wheel / RB Turbos / M3 CF Roof / Brembo GT BBK 355/345 / Rollcage / Forge FMIC / Quaife LSD / Íhlins Road & Track / M3 Suspension Parts / Powerflex Bushings / Vorshlag Camberplates / Megan Racing Toe Links / LeatherZ Gauges / Extended M3 DCT Paddles / ER Sports OC / AR OC / Aux Radiator / AR DPs / Alpina TCU / COBB Pro-Tune
Autobahn335i is offline   Luxembourg
Reply With Quote
      05-14-2010, 12:36 PM   #4
Brigadier General
Fraggy's Avatar
Drives: 2007 e90
Join Date: Jun 2005
Location: San Diego

Posts: 3,312
iTrader: (11)

Good to hear. I so want to do them but worry about the ride stiffness. But the jiggly rear kinda drives me nuts sometimes. I dont track, just like a nice feeling car.
Step--Premium--Sport--Nav--20% Tint--Blacklines--18" Beyern Mesh--Michelin Super Sports--Bastuck Exhaust--M3 Steering Wheel--BMW Performance Springs--Koni--M3 Front/Rear Sways--
Fraggy is offline   United_States
Reply With Quote
      05-14-2010, 01:16 PM   #5
stressdoc's Avatar
Drives: F80 YMB
Join Date: Jun 2005
Location: MO

Posts: 10,127
iTrader: (0)

Get a LSD.
stressdoc is offline   Dominica
Reply With Quote
      05-14-2010, 02:00 PM   #6
Sparky66's Avatar
Drives: 335 E92 Coupe. Jet Black.
Join Date: Feb 2007
Location: Sydney, Australia

Posts: 1,232
iTrader: (0)

If your car wanders around under hard accelleration, like Stressdoc said......get an LSD first. It will get rid of most of the wandering and you get to retain your cars original ride quality. If you then want to further improve corner handling, look at a good coilover setup like the PSS10 Bilsteins and then if you want more again, a decent set of swaybars like the M3 setup.
That's the order I would go, as you may be more than happy with just an LSD. Going in stages is the best way to find your happy medium.
Sparky66 is offline   Australia
Reply With Quote
      05-14-2010, 08:42 PM   #7
Drives: 4 Door Family Sedan
Join Date: Sep 2009
Location: Minneapolis

Posts: 2,429
iTrader: (7)

I'll agree completely with the LSD...I'm just trying to justify it to myself to spend the $2600 for it. (Damn welded ring gear)

As for the rear swaybar...I wouldn't recommend it without an LSD...I"m somewhat regretting it as it spins the inside tire just about every turn.

Again, the very small increase of ride stiffness is well worth it in my opinion. It's not that it's jarring and bumpy...you just notice the roads imperfections more.

I went on a rally session today and said WOW all over again. When accelerating in 1st gear and shifting to second, it feels SOOO much better! Almost like a more rigid feeling, but not jerky.

BrianMN is offline  
Reply With Quote
      05-15-2010, 10:47 PM   #8
"I know you know that I know you know..."
T7R_Sky's Avatar
Drives: Sparkling Graphite E90 328i
Join Date: Mar 2006
Location: Escondido, CA

Posts: 795
iTrader: (3)

Garage List
2008 E90 328i  [0.00]
Send a message via AIM to T7R_Sky
Woah! How did you remove the rear subframe! I've always wanted to do this but thought it was too big a problem to deal with. Can you pm me a DIY of sorts so I can do this for my car! Thanks in advance!
T7R_Sky is offline   United_States
Reply With Quote


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
Forum Jump

All times are GMT -5. The time now is 03:15 AM.

Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
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