[GeoFX]

Just installed M3 front control arms on my 2011 E92 MSport and am looking to balance those out with stiffer rear subframe bushings. These will me mated to Bilstein HD dampers.

Thoughts on oem M3 vs. Powerflex Yellow rear bushings? Any significant difference between the two other than ones rubber and the other is poly? From what i've read they have the same stiffness.

Real-world experiences are appreiciated!

[Fundguy1]

Plenty of threads on this. Most say go stiffer. Current generation uses solid bushings. I'm going solid. I'd go black at least. BMW makes upgraded ones for our generation M3 for a reason.
http://www.e90post.com/forums/showthread.php?t=1055253

[GeoFX]

Originally Posted by Fundguy1

Plenty of threads on this. Most say go stiffer. Current generation uses solid bushings. I'm going solid. I'd go black at least. BMW makes upgraded ones for our generation M3 for a reason.

They make solid M3 rear subframe bushings for E92s now? Are you talking about the BMW Motorsports versions?

Looking to put these on a daily driver (no track) so want to make a few sacrifices to NVH as possible. Just looking to balance out the new control arms, that's all.

[Fundguy1]

I'd go black then. Current generation M3 and M4 have solid as stock. Haven't heard any NVH from black and minimal from solid on our chassis. Mine is daily and I'm going solid. Read the link.

[andrey_gta]

Powerflex are single piece bushings and may be harder to is tall than a whiteline two piece bushing. So factor that in for poly and poly alternatives

[GeoFX]

so no love for the oem M3 bushies? seems like it's the most popular rear bushing mod on the forum

[feuer]

You don't track your car so stiffer especially solid bushings would be kind of a waste honestly. Is true as above mantioned that f30 uses solid mounts but also the rest of the rear suspension is designed differently so no comparasion. Solid will unveil other "soft" areas. Is like domino effect. I would recommend inserts for the subframe bushings and monroe upper shock mounts. Also, I will advise you to do another alignement because the chances are that the cross axles aligment will be off after messing with the rear subframe.

[LMB335IS]

Originally Posted by GeoFX

so no love for the oem M3 bushies? seems like it's the most popular rear bushing mod on the forum

M3 are definitely better than stock but if you're going to install them yourself I personally would want to install the best solution the first time. I did powerflex black and with runcraps you could feel the road like your ass was being dragged across it but now with "real" tires the harshness is gone. The ass end behaves like it should have from the factory now.

[Fundguy1]

I agree about all being better than stick. But the subframe bushings are a big deal to change. This is definitely a case of do it once do it right. I would choose the highest you want to possibly go the first time. Definitely at least the black or higher.

[GeoFX]

Originally Posted by feuer

You don't track your car so stiffer especially solid bushings would be kind of a waste honestly. Is true as above mantioned that f30 uses solid mounts but also the rest of the rear suspension is designed differently so no comparasion. Solid will unveil other "soft" areas. Is like domino effect. I would recommend inserts for the subframe bushings and monroe upper shock mounts. Also, I will advise you to do another alignement because the chances are that the cross axles aligment will be off after messing with the rear subframe.

Thanks. I read about the Monroe Upper shock mounts and they seem to be a very inexpensive mod to help stiffen up the rear end (at $24 for the set, it's a no-brainer), esp. since I've just recently put in the Bilstein HD shocks.

What bushing inserts are you talking about? The Whitelines or Powerflex? Seems like there is contradictory info out there about how much labor is involved..one thread says the Whitelines take about 1-2 hours to install and the Powerflex takes 5-6 (which at that point why not just go with the bushings instead of inserts).

Here's a link to the Powerflex insert install (should be the same as the Whitelines I would've thought) - http://www.e90post.com/forums/showthread.php?t=543295

[feuer]

Originally Posted by GeoFX

Thanks. I read about the Monroe Upper shock mounts and they seem to be a very inexpensive mod to help stiffen up the rear end (at $24 for the set, it's a no-brainer), esp. since I've just recently put in the Bilstein HD shocks.

What bushing inserts are you talking about? The Whitelines or Powerflex? Seems like there is contradictory info out there about how much labor is involved..one thread says the Whitelines take about 1-2 hours to install and the Powerflex takes 5-6 (which at that point why not just go with the bushings instead of inserts)

All depends how mechanically inclined you are.
Inserts take 1-2h (whiteline and PowerFlex are same shape, they have to be)
Replacing the bushings will take 5-6h.
Also, you don't need specialty tools for the inserts.

[jjellyneck]

I installed the Whiteline subframe inserts. Not too difficult, but the positive difference in handling and feel was very big. Well worth it.

[chris82]

I like the M3 ones I have. They were a huge upgrade over stock. If you don't track the car, there really is no need to upgrade to anything stiffer than the M3 ones and honestly, I trust an OE BMW part over any other alternatives if you want longevity or reliability. This is not something you want to have to replace in the future.

[GeoFX]

Had a local mechanic install the Whiteline bushing inserts and the Monroe 907984 rear upper strut mounts today. Combined with the Bilstein HD/OEM Sport springs combo that were put on a couple months ago, there's a noticeable difference in reduced squat and floatiness.

Good and relatively cheap upgrades for someone who doesn't track their vehicles but am looking for a firmer, more responsive ride.

[feuer]

I'm glad you took my advice and you like the result which for the money is great! Awesome! Enjoy your ride!

[dbworld4k]

I've begun tracking my car and was just debating this myself. I have Ohlins coilovers and M3 F+R upper & lower control arms and F+R M3 sways. I'm dropping the subframe for a LSD install and would like to tackle this at the same time. My car is a daily driver but I would like to make it more sportier (evidently). Would the M3 bushings do the job or am i wasting my time and money and should get Powerflex?

[Fundguy1]

Powerflex or AKE black.

[Jaronbwall]

Originally Posted by Fundguy1

Powerflex or AKE black.

What's a rough estimate for the cost of installing subframe inserts?

[Tom Droze]

Originally Posted by Jarronbwall

What's a rough estimate for the cost of installing subframe inserts?

It should only take a qualified technician about one hour to install the inserts. I did it in my garage in 1 1/2 hours.

[Fundguy1]

1-2 hours on inserts. Not much difference vs stock on a relative basis vs full inserts. Full inserts 5-6 hours labor. AKE black going in this week on mine.