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
 
GT Haus
Post Reply
 
Thread Tools Search this Thread
      01-09-2014, 08:13 PM   #1
esquire
Colonel
esquire's Avatar
United_States
58
Rep
2,801
Posts

 
Drives: 2011.5 Dakar Yellow M3 Coupe
Join Date: Feb 2007
Location: Orange County, California

iTrader: (0)

MRF Solid Sub-Frame & Differential Bushings - A Night & Day Difference in Performance

Some of you are familiar with my build. Over the years, its become more and more focused on extracting maximum performance out of the car. (Full build thread HERE)

The first mod in that direction was KW Clubsports. Then an ESS VT2-625. Then I managed to get my hands on one of MRF's rare X-Pipe. Together that combo has made my car a bit of a freak in the horsepower realm, dynoing 581HP/377TQ on 91 Octane. (See MRF X-Pipe dyno gains HERE).

Its one thing to put down a lot of horsepower on a dyno. But its another thing altogether to get the same power down on the road, where traction, wheel-spin, and wheel hop come into play. Because of how much power I was putting down, first gear basically became non-existent. Accelerating from a dig, I couldn't hook up with the road without a lot of wheelspin. When I did finally hookup, my tail would either kick in one direciton or I'd get a lot of wheel hop, before the car could put down power properly. And even then, I'd have to short-shift out of first around 5k rpms before the car broke traction again. I began feeling like: "what's the point of my supercharger if i can't translate its power to real world results?"

I contacted MRF Engineering, who (as a lot of you know) is a shop that has made a name for itself for serious performance builds and track builds - i.e. serious project cars - and they recommended that I look into replacing the OEM sub-frame bushings and differential bushings with solid ones (Aluminum for the sub-frame bushings, Delrin for the differential bushings). They explained that the bushings would substantially improve how much power the car could put down, by minimizing wheel hop, car squat, and diff deflection

I was skeptical. How much difference could a hunk of aluminum or Delrin make?.....

Turns out... A LOT !!

Results:
Performance improvements were drastic. The way the car handles and puts down power now, is like night and day. Here are some of the many improvements I've noted. My car:
  1. puts down A LOT more power now in first gear,
  2. puts that power down much more reliably and predictably (which is very confidence inspiring),
  3. puts that power down without nearly as much wheelspin or traction breaking in first gear, and eliminate wheelspin and traction breaking in second gear altogether (whereas before there was some),
  4. gives me a lot more usable RPM in first gear (before I would have to short-shift out of first at 5k, now I can shift out around 7.5k RPMs).
  5. wheelhop is eliminated
  6. squat under heavy acceleration is eliminated
  7. tail does not shift under heavy acceleration

The car should have come like this in the first place. It comes as no suprise, that subsequently BMW has begun putting these solid bushings in their other performance cars (including the M3 GTS, the new M5 and new m6). While I, personally, can't comment on the results for NA cars, the benefits are so universal that I have to imagine substantial improvements for NA cars as well. And NA people have said the same in other reviews. My car now feels much more sure-footed, planted, reliable, and most importantly, I have access to much more useable power from the line. If you care about performance, GET THIS MOD.


The Parts:
The sub-frame bushings are custom designed by MRF engineering, and C&C'd from solid aluminum. They're beautiful pieces. Too bad they're completely hidden from view once installed. Here is a pic:

MRF Aluminum Subframe Bushings
Name:  IMG_7937.jpg
Views: 1350
Size:  289.9 KB



OEM Subframe Bushings
Name:  IMG_9070.jpg
Views: 1239
Size:  363.1 KB


By contrast, the differential bushings are made of delrin - so they have just an infinitessimal bit more "give" than aluminum. Aluminum differential bushings are also available to those who really want them. Both the aluminum and delrin differential bushings (not the sub-frame bushings) are from Turner Motorsports.


Comments on NVH (Noise, Vibration, Harshness) -
This is a performance mod. As with any performance mod, there is a bit of a trade off in "comfort." People need to be honest with themselves about that upfront. Buy an exhuast, you get a louder car, and sometimes drone. Buy new shocks or a coilover kit, you get a stiffer less forgiving car. Buy a supercharger, you're gonna hear some supercharger noise. BMW dumbs this car down, and makes it more cushy for the masses. If you want to tap into the car's full potential, you have to get rid of some of BMW's "lowest-common-denominator" creature comforts. Luckily, the trade-off here is minimal.

The bushings do create a low volume whine above 40mph and 3k RPM for me. (Might be different for other people). Best way to describe the sound is that it sounds like the F1 car noise, but just on low volume. Its actually kind of cool. But if you're looking for dead silence - this is not it.

I have both the sub-frame and differential bushings so I can't pinpoint exactly WHICH of the two is causing the F1 type noise, but my understanding that it is strictly associated with the differential bushings and that the sub-frame bushings do not contribute to this noise.

For those curious about how prominent the noise is - its entirely imperceptible if you're listening to music, or if your windows are rolled down.

I will try to put a video up of the sound inside the cabin for those who are curious, sometime in the next few days.

The question I always ask myself on any mod is: "is what I'm gaining worth more than what I'm sacrificing?". With the solid bushings, the answer to me was an overwhelming yes. I can't communicate how truly pleased I am with the results.




Pics from the Installation:









As you can see, the Sub-Frame comes out for this install. Luckily MRF Engineering has some very expensive custom tools at their disposal (being a performance oriented shop) - and can get what would otherwise be a very long install, done relatively quickly. That saves us (the consumer) money and time. Unsurprisingly, other shops that aren't quite as performance oriented just don't have these tools. This month alone, I understand Malek has already done 8 (!) of these installations. And all of their reviews appear to be universally as glowing as mine. Probably a good reason for that.



Best,
- esquire
__________________

[ESS VT2-625] [Akrapovic Evolution Exhaust] [KW Clubsports] [OSS Angel Eyes] [Revinora r-CRT Lip]
[Vorsteiner Boot] [Challenge Race Diffuser] [See the Build Thread HERE]

Last edited by esquire; 01-09-2014 at 08:34 PM.
Appreciate 0
      01-09-2014, 08:49 PM   #2
tmntmn
///M
United_States
44
Rep
1,903
Posts

 
Drives: e92 M3/M-DCT
Join Date: Feb 2008
Location: Bay Area

iTrader: (6)

Very detailed review about the subframe upgrade!, been reading a lot of forum member with SC m3 upgrade their subframe recently.

I'm trying to keep my car N/a and was wondering if its worth it to do the upgrade.
__________________
THANKS TO:~<RPM>~ ~<SONICMS>~ ~<MODECARBON>~ ~<McKennaPerformance>~
MODS: MODECARBON V2 GTS FRONT LIP & REAR DIFFUSER, AA GREEN FILTER, RPI SCOOPS, PSW, Verstraβe Extended DCT Shifter, ZCP WHEELS (SEMI-GLOSS), OHLINS R&T, Megan Exhaust, ACM TP, BMW LED INTERIOR, BLACKOUT W/ORION V4 LED AE, OSRAM CBI
Appreciate 0
      01-09-2014, 08:54 PM   #3
esquire
Colonel
esquire's Avatar
United_States
58
Rep
2,801
Posts

 
Drives: 2011.5 Dakar Yellow M3 Coupe
Join Date: Feb 2007
Location: Orange County, California

iTrader: (0)

Quote:
Originally Posted by tmntmn View Post
Very detailed review about the subframe upgrade!, been reading a lot of forum member with SC m3 upgrade their subframe recently.

I'm trying to keep my car N/a and was wondering if its worth it to do the upgrade.
That's really a question of whether you feel your car is capably putting power down in first gear. Part of that has to do with how much power you have. Part of that is also how aggressively you drive. Some members are making a good amount of power NA, I would say this mod is for them. Some members also like to mash the pedal off the line, I would say this mod is also for them.

Like I mentioned in my post, there are several NA cars out there who have done their bushings, and I believe they have all had positive things to say about the mod.
__________________

[ESS VT2-625] [Akrapovic Evolution Exhaust] [KW Clubsports] [OSS Angel Eyes] [Revinora r-CRT Lip]
[Vorsteiner Boot] [Challenge Race Diffuser] [See the Build Thread HERE]
Appreciate 0
      01-09-2014, 09:23 PM   #4
BarryC
Major
United_States
42
Rep
1,160
Posts

 
Drives: '13 LRP M3
Join Date: May 2007
Location: Kernersville NC

iTrader: (10)

Nice review! Regarding wheel hop - did these mods eliminate or reduce it?

Thanks!
BC
__________________
2014 M5
Appreciate 0
      01-09-2014, 09:56 PM   #5
BESTNDA416
Captain
BESTNDA416's Avatar
Canada
8
Rep
648
Posts

 
Drives: ESS VT3 750 E92
Join Date: Sep 2012
Location: Toronto

iTrader: (4)

Garage List
2008 E92 M3  [4.83]
More and more I read about this the more it keeps pushing me to buy these. Thanks for the great review
Appreciate 0
      01-09-2014, 10:00 PM   #6
esquire
Colonel
esquire's Avatar
United_States
58
Rep
2,801
Posts

 
Drives: 2011.5 Dakar Yellow M3 Coupe
Join Date: Feb 2007
Location: Orange County, California

iTrader: (0)

Quote:
Originally Posted by BarryC
Nice review! Regarding wheel hop - did these mods eliminate or reduce it?

Thanks!
BC
I have yet to experience any wheel hop whatsoever
__________________

[ESS VT2-625] [Akrapovic Evolution Exhaust] [KW Clubsports] [OSS Angel Eyes] [Revinora r-CRT Lip]
[Vorsteiner Boot] [Challenge Race Diffuser] [See the Build Thread HERE]
Appreciate 0
      01-09-2014, 10:45 PM   #7
ibmike
What the Hell ?
ibmike's Avatar
United_States
17
Rep
1,518
Posts

 
Drives: 2011 M3 e92 DCT
Join Date: May 2013
Location: Michigan

iTrader: (6)

Sweet, great info, isnt there some companies that make super hard but not soild differential bushings? How long did it take and what was the Total cost?
__________________
Life's a Bitch,Just make sure that Bitch is Beautiful.
Appreciate 0
      01-09-2014, 11:22 PM   #8
schnell325
Bored at work....
schnell325's Avatar
Canada
43
Rep
3,875
Posts

 
Drives: '08 M3,'11 335xi
Join Date: Aug 2007
Location: BC

iTrader: (5)

Wonderful review. You've made up my mind 100%.

May I ask the price of the sub frame bushings and the diff bushings?

PM me if you wish
Appreciate 0
      01-09-2014, 11:33 PM   #9
spdy330
Major General
spdy330's Avatar
United_States
100
Rep
6,074
Posts

 
Drives: 05 Tundra, 11 M3, 08 Odyssey
Join Date: Dec 2009
Location: Chino, CA

iTrader: (161)

Garage List
Send a message via AIM to spdy330 Send a message via Yahoo to spdy330
Sounds expensive.
__________________
If you will be purchasing ANY AT&T services online or in store could you mention that you were referred by me? My Employee Referral ID is eo4489. This would be a great help and it costs you nothing, thank you!
Appreciate 0
      01-10-2014, 12:03 AM   #10
JEllis
Brigadier General
JEllis's Avatar
84
Rep
4,783
Posts

 
Drives: E36 M3, E92 M3
Join Date: Oct 2006
Location: SD CA/Yuma

iTrader: (4)

SWEET review!
__________________
http://www.m3post.com/forums/signaturepics/sigpic14547_7.gif
Appreciate 0
      01-10-2014, 12:20 AM   #11
Pertplus
Colonel
Pertplus's Avatar
United_States
46
Rep
2,387
Posts

 
Drives: 2014 991 Turbo S
Join Date: Jun 2013
Location: San Diego, California

iTrader: (7)

Garage List
2015 M235i  [0.00]
2014 Porsche 991 C2S  [5.00]
Love mine! And I don't notice any whine!
Appreciate 0
      01-10-2014, 12:20 AM   #12
flipm3
E46 + E90
Philippines
43
Rep
2,788
Posts

 
Drives: E46 M3 + E90 M3
Join Date: Jul 2008
Location: Illinois

iTrader: (1)

Garage List
2009 BMW M3  [0.00]
2002 BMW M3  [0.00]
Incredible review as always.

If it's possible to make a video, that would truly be appreciated!
__________________
E90 M3 DCT|Melbourne Red . Speed Cloth | My Build Thread
E46 M3 6MT|Jet Black . Black Nappa Leather | My Build Thread
Appreciate 0
      01-10-2014, 01:05 AM   #13
esquire
Colonel
esquire's Avatar
United_States
58
Rep
2,801
Posts

 
Drives: 2011.5 Dakar Yellow M3 Coupe
Join Date: Feb 2007
Location: Orange County, California

iTrader: (0)

Quote:
Originally Posted by flipm3
Incredible review as always.

If it's possible to make a video, that would truly be appreciated!
Will do !
__________________

[ESS VT2-625] [Akrapovic Evolution Exhaust] [KW Clubsports] [OSS Angel Eyes] [Revinora r-CRT Lip]
[Vorsteiner Boot] [Challenge Race Diffuser] [See the Build Thread HERE]
Appreciate 0
      01-10-2014, 01:12 AM   #14
schnell325
Bored at work....
schnell325's Avatar
Canada
43
Rep
3,875
Posts

 
Drives: '08 M3,'11 335xi
Join Date: Aug 2007
Location: BC

iTrader: (5)

Quote:
Originally Posted by esquire View Post
Will do !
I'll reply tomorrow!!


Appreciate 0
      01-10-2014, 10:01 AM   #15
Wendall
***Major MammelToe
Wendall's Avatar
United_States
37
Rep
1,146
Posts

 
Drives: E92 M3 SG coupe
Join Date: Feb 2012
Location: Orange County, CA

iTrader: (3)

Quote:
Originally Posted by Pertplus View Post
Love mine! And I don't notice any whine!
My whine is faint. Actually, I would like it louder! Its sounds like a baby F1.
__________________
E92 M3 SG DCT - AA Filter, Verstraβe Paddles, ECS SS, MH race stud, Stoptech BBK, MR Exhaust,RE Pulley, BPM Tune,Euro bumper and GTS lip, Euro MDM & DCT, KW CS, Recaro PP, TMS Soild Diff Mounts, MRF solid subframe mounts, GTS aero, RPM track built motor.

Appreciate 0
      01-10-2014, 10:12 AM   #16
flipm3
E46 + E90
Philippines
43
Rep
2,788
Posts

 
Drives: E46 M3 + E90 M3
Join Date: Jul 2008
Location: Illinois

iTrader: (1)

Garage List
2009 BMW M3  [0.00]
2002 BMW M3  [0.00]
Quote:
Originally Posted by esquire View Post
Will do !
Thanks! I truly enjoy your write ups on the forum.

Quote:
Originally Posted by biggynuts01 View Post
My whine is faint. Actually, I would like it louder! Its sounds like a baby F1.
I want a F1 Baby!
__________________
E90 M3 DCT|Melbourne Red . Speed Cloth | My Build Thread
E46 M3 6MT|Jet Black . Black Nappa Leather | My Build Thread
Appreciate 0
      01-10-2014, 10:19 AM   #17
Pertplus
Colonel
Pertplus's Avatar
United_States
46
Rep
2,387
Posts

 
Drives: 2014 991 Turbo S
Join Date: Jun 2013
Location: San Diego, California

iTrader: (7)

Garage List
2015 M235i  [0.00]
2014 Porsche 991 C2S  [5.00]
Quote:
Originally Posted by biggynuts01
Quote:
Originally Posted by Pertplus View Post
Love mine! And I don't notice any whine!
My whine is faint. Actually, I would like it louder! Its sounds like a baby F1.
I do notice a lot of stiffness. But that's all coming from my lower pants region whenever I drive this MRF built monster
Appreciate 0
      01-10-2014, 04:49 PM   #18
esquire
Colonel
esquire's Avatar
United_States
58
Rep
2,801
Posts

 
Drives: 2011.5 Dakar Yellow M3 Coupe
Join Date: Feb 2007
Location: Orange County, California

iTrader: (0)

Quote:
Originally Posted by Pertplus View Post
Love mine! And I don't notice any whine!
Pert, did you get both the subframe and the differential bushings? Goes to those that the noise is so faint that on some cars its completely non-existent.


Quote:
Originally Posted by Pertplus View Post
I do notice a lot of stiffness. But that's all coming from my lower pants region whenever I drive this MRF built monster
Lol.
__________________

[ESS VT2-625] [Akrapovic Evolution Exhaust] [KW Clubsports] [OSS Angel Eyes] [Revinora r-CRT Lip]
[Vorsteiner Boot] [Challenge Race Diffuser] [See the Build Thread HERE]
Appreciate 0
      01-10-2014, 05:21 PM   #19
Pertplus
Colonel
Pertplus's Avatar
United_States
46
Rep
2,387
Posts

 
Drives: 2014 991 Turbo S
Join Date: Jun 2013
Location: San Diego, California

iTrader: (7)

Garage List
2015 M235i  [0.00]
2014 Porsche 991 C2S  [5.00]
Quote:
Originally Posted by esquire View Post
Pert, did you get both the subframe and the differential bushings? Goes to those that the noise is so faint that on some cars its completely non-existent.




Lol.
Yes I believe I got both...
Appreciate 0
      01-11-2014, 08:06 PM   #20
Brian0473
First Lieutenant
Brian0473's Avatar
4
Rep
350
Posts

 
Drives: 2010 SSII DCT Coupe
Join Date: Sep 2013
Location: San Antonio, TX

iTrader: (4)

Would be interesting to see before/after performance measurements, i.e. 0-60, 60ft. times, 1/4 mile, to see what the actual improvements are to acceleration.
__________________
'10 SSII/Fox Red M3 DCT (Forgeline GA1R 19's,Stop Tech BBK,Eibach,AA Green Filter,Full Akra Evo+DeleteR,GTS DCT Tune, a few other cosmetic goodies)
'92 Spec Miata (At Track); '11 F150 (Outside).

Appreciate 0
      01-15-2014, 05:49 PM   #21
Malek@MRF
BimmerPost Supporting Vendor
Malek@MRF's Avatar
United_States
62
Rep
3,406
Posts


 
Drives: E92 M3, E46 M3, F30, E30
Join Date: Jan 2008
Location: Irvine, California

iTrader: (5)

Send a message via AIM to Malek@MRF
Sasan,

Glad you are enjoying your new bushings.

For those wondering if this is only for Supercharged cars, the answer is a resounding no. The Sub-frame bushings equally benefit the naturally aspirated cars as all the same rear end problems are still present. The forced induction guys simply notice more of a grip difference in comparison to the N/A guys because most N/A cars don't have traction issues in comparison to SC'd cars.

All the other benefits are identical.
__________________

BMW PERFORMANCE SPECIALISTS. Suspension. Forced Induction. Brakes. Race Preparation. Service. Alignments.
OFFICIAL PARTNERS: Íhlins. KW Suspension. Brembo. AP Racing. ESS Tuning. iND Distribution. Turner Motorsport.
Facebook | Instagram | Yelp! | Flikr | Contact | YouTube
Appreciate 0
      01-15-2014, 07:36 PM   #22
klammer
Brigadier General
41
Rep
3,245
Posts

 
Drives: 11 spc gry m3 e90, 07 X5
Join Date: Jan 2010
Location: chicago

iTrader: (0)

I've gone delrin (they felt like metal to me) subframe bushings and I'm NA and just did this as my car sees a lot of track time. Did a rear sway install at the same time (that I've subsequently snapped at the bar ,not end links ) and can say I love the solid, responsive feel of the back end and that the whole car just feels that much more responsive and communicative at the limit. Did a 1700 mile round trip days after install with the wife and kids (out to VIR last year) and felt no difference cruising around and neither did my wife. Stayed away from the diff upgrade as I've heard that's what adds the most NVH, (besides the engine ones) and have never once done launch control and don't plan on it, so subframe for me...great writeup
__________________
mods: akra evo, dinan 3.45 diff, ess akra tune, dinan stg.3, Alcon bbk, HRE P40
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
Forum Jump


All times are GMT -5. The time now is 02:24 AM.




m3post
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