rear powerflex bushes

acerboo · 06-05-2015, 04:38 PM

has anyone replaced rear bushes with powerflex

Jules59 · 06-05-2015, 07:13 PM

I have some but never got round to changing them - seem really difficult to get at compared to the fronts.

acerboo · 06-06-2015, 12:22 PM

just wondering if theres that much benefit to fitting them

idnan · 06-08-2015, 04:09 PM

Subframe bushes? Diff bushes? or Rear arm bushes?

acerboo · 06-08-2015, 04:35 PM

don't know if some or all need replacing. was thinking just the ones that could affect the steering. I gather some can?

Icekube · 06-09-2015, 06:24 AM

just fit new OEM bushes.

poly's are just overkill, and dont actually work properly.

mob17 · 06-09-2015, 12:27 PM

Quote:

Originally Posted by Icekube

just fit new OEM bushes.

poly's are just overkill, and dont actually work properly.

I'm considering solid aluminium subframe bushes....

Aragorn30d · 06-09-2015, 02:37 PM

I did solid subframe bushes on my old car and regretted it. Too harsh, too much noise and vibration transmitted into the cabin etc.

Go with OEM, M3 ones are probably a decent upgrade without going overkill.

mob17 · 06-09-2015, 04:11 PM

Quote:

Originally Posted by Aragorn30d

I did solid subframe bushes on my old car and regretted it. Too harsh, too much noise and vibration transmitted into the cabin etc.

Go with OEM, M3 ones are probably a decent upgrade without going overkill.

What car did you put them on?

There was a review on solid aluminium bushes on the suspension forum, and the guy basically said no NVH increase. A few members were saying they regret puttin M3 ones on as they were too soft, but i guess everyone is different!

I do have stiffer rear springs going on soon, which will hopefully help a lot. At the mo the rear is too soft and flimsy due to the amount of torque im running, which is why i thought solid would be the best chance i have of locking it all up. But a lot of NVH wouldn't be good...

Aragorn30d · 06-09-2015, 05:04 PM

They're on my B5 A4 Quattro.

For me the solid bushes amplified the small amount of slack that exists in the drivetrain, and turned it into horrible harshness. Make a fast gearchange under power and you get an almighty bang from the rear end as you re-engage the clutch, because everythings so rigidly mounted theres no slack to absorb the shock loadings. I had solid (high density rubber, not aluminium) diff mounts in the car as well which i ended up removing as it was so bad.

I guess it depends on what your doing with the car. Yours is a diesel, which lets face it isnt a "sports" car. Its a fast smooth everyday luxury car. Going full on race mode with solid bushings etc will IMO simply ruin what the car is. But maybe you view the car differently to me. If it was a weekender M3 or 335i that you did a lot of track work with then it would be a different story.

People often forget, that when BMW built the M3, and reviewers took that car out and kicked its arse, they didnt all start whining about how the suspension was too soggy and it needed rock hard bushes. These cars are universally acclaimed as hitting the nail on the head when it comes to handling and as an all round package.

When mine has bits wear out and needs replacements, it'll be getting M3 bits or OEM.

mob17 · 06-09-2015, 06:14 PM

Quote:

Originally Posted by Aragorn30d

They're on my B5 A4 Quattro.

For me the solid bushes amplified the small amount of slack that exists in the drivetrain, and turned it into horrible harshness. Make a fast gearchange under power and you get an almighty bang from the rear end as you re-engage the clutch, because everythings so rigidly mounted theres no slack to absorb the shock loadings. I had solid (high density rubber, not aluminium) diff mounts in the car as well which i ended up removing as it was so bad.

I guess it depends on what your doing with the car. Yours is a diesel, which lets face it isnt a "sports" car. Its a fast smooth everyday luxury car. Going full on race mode with solid bushings etc will IMO simply ruin what the car is. But maybe you view the car differently to me. If it was a weekender M3 or 335i that you did a lot of track work with then it would be a different story.

People often forget, that when BMW built the M3, and reviewers took that car out and kicked its arse, they didnt all start whining about how the suspension was too soggy and it needed rock hard bushes. These cars are universally acclaimed as hitting the nail on the head when it comes to handling and as an all round package.

When mine has bits wear out and needs replacements, it'll be getting M3 bits or OEM.

Ooo that does sound bad on your Audi. But its kinda hard to compare aluminium bushes and harder diff bushes on a different car like an Audi to an E9X.

I think you view my car as a stock 335d. Mine is certainly not a track car, but equally it's certainly not an everyday diesel like you are making it out to be. Even stock 335d isnt an everday diesel. Yes mine is a diesel but it would piss on a M3 on straight line (haven't tested in corners yet). It's on over 420bhp, and the chassis could do with upgrading. Not talking about full on race mode, just aluminium subframe bushes. But i'm not sure whether i should upgrade to M3 or aluminium, as i wouldn't want to do M3 and then think wish i went further. But then again as you say nothing wrong with M3 cars and aluminium could be OTT.

But people who have tried aluminium subframe bushes on an E9X say they are fine and no increase in NVH. On the M4 the rear subframe doesnt have bushes, there are solid bolts, which is making me go towards the solid bushes route...but again M4 is a different platform like the Audi!

But it will be a while until i upgrade them, hopefully a few people who have put aluminium subframe bushes on an E9X can give some feedback until then. Not in a rush, have a baby on the way soon!

OP sorry for the thread jack.

idnan · 06-10-2015, 03:30 PM

Mob I have some AKG 75d rear subframe bushes with less than 1000 miles on them if you're interested. Same as these ones half way down the page:

http://www.akgmotorsport.com/catalog...ion%2FBushings

I have aluminium diff bushes, m3 diff and with these the whine was quite loud. I changed to softer Whiteline subframe bushes and they are slightly less harsh and is what I settled on.

mob17 · 06-10-2015, 05:50 PM

Quote:

Originally Posted by idnan

Mob I have some AKG 75d rear subframe bushes with less than 1000 miles on them if you're interested. Same as these ones half way down the page:

http://www.akgmotorsport.com/catalog...ion%2FBushings

I have aluminium diff bushes, m3 diff and with these the whine was quite loud. I changed to softer Whiteline subframe bushes and they are slightly less harsh and is what I settled on.

How much are you after? And how much did you pay for fitting? PM me if you want.

I just get a lot of movement from the rear at WOT, worse than when it was on stock power. It's like trying to ride a crazy bull sometimes.

mob17 · 06-12-2015, 03:23 AM

Quote:

Originally Posted by Aragorn30d

People often forget, that when BMW built the M3, and reviewers took that car out and kicked its arse, they didnt all start whining about how the suspension was too soggy and it needed rock hard bushes. These cars are universally acclaimed as hitting the nail on the head when it comes to handling and as an all round package.

When mine has bits wear out and needs replacements, it'll be getting M3 bits or OEM.

Try telling that to the M3 owners who actually live with and drive their cars the way it should. They are upgrading their subframe bushes too, and diff bushes. Maybe you should try and convince them not to and point our your M3 review

:

Idnan, pm replied.

Aragorn30d · 06-12-2015, 09:52 AM

What your essentially saying, is that BMW M dont know what they're doing, the millions they spent on R&D was pointless and you need to clag in some "upgrade" parts that someone spun up on a lathe in a half hour because they're solid and must be better.

Sure, BMW M probably left some performance on the table, but they're producing a high performance road car, which if i'm not mistake is also what you own. If its a dedicated track toy or going even further a race car, then you make changes which seriously detract from the everyday driveability of the car for the last n% of performance. For a road car, you need to find the perfect balance between all the elements.

What i'm trying to get across is that its all a very fine line, and what your doing is taking a car full of worn out parts (because after-all, its not new, its driven many thousands of miles over many years) assuming thats representative of how it should be, and thus coming to the conclusion that huge upgrades need to be made because the standard parts are crap.

Infact, replacing everything with new standard bits would likely make a huge improvement, and replacing those with the M3 parts would likely make a further improvement again, and you can do all of that with zero impact on drivability because BMW ensured it to be so.

The guy your buying the bushes from has already said he's removed them from his car and replaced them with softer ones because it transmitted too much noise into the cabin, but you seem convinced that it'll be rosy.

mob17 · 06-12-2015, 03:24 PM

I disagree with pretty much everything you have said. What are you basing your thoughts on? First hand experience or BMW M3 reviews you read online? You're also basing your opinion on the assumption that my car is stock, it's not, it has more power and over twice the torque than an E92 M3. That's a significant factor! Think about the stresses on the rear subframe. Do you really think M3 bushes, never mine new OEM ones, are designed to handle twice the torque without giving a lot of flex? Even M3 owners on stock M3 power are finding benefits of solid bushes.

I tell you what i base my thoughts on. Fellow members on here who are driving higher powered cars than you and I that have upgraded their non-M bushes to solid bushes. M3 owners have also upgraded from M3 to solid. Maybe you should go on M3 cutters or M3post and say people are ruining the everyday drivability by upgrading their M3 bushes. Would love to see the response.

I am running over 420bhp and I need to upgrade my subframe bushes. I know my car and i can feel it going sideways at WOT. Hell, i could even feel the rear moving about and skipping before my power upgrade. Maybe if you had a more powerful car you would understand, or maybe your car is powerful enough and you just either drive like a granny everywhere or just don't realise what is happening at the rear, i don’t know. But what i do know it's not due to worn bushes. Remember the OEM non-M bushes, and most of the suspension, was designed for run flats.

And about idnan. His case is different. Why? Because he has solid aluminium diff bushes which are very well known to increase NVH. If you have solid diff AND subframe bushes then yes there would be a lot of NVH and it's a good idea to soften one of the two. Which is what idnan is doing i assume. If diff bushes are kept OEM (or slightly stiffened to poly), then the NVH with solid subframe bushes will be very minimal, hard to detect -> this according to people who have actually got solid aluminium bushes on an E9X platform, M and Non-M.

Sources here FYI and anyone reading:

Fellow 335i driver upgrading to solid aluminium bushes:
http://www.e90post.com/forums/showthread.php?t=1125661

Fellow M3 drivers upgrading their M3 subframe bushes to solid aluminium:
www.m3post.com/forums/showthread.php?t=926758

Long discussion on various subframe and diff bushes:
http://www.e90post.com/forums/showthread.php?t=1055253

Discussion of solid Subframe bushes on E9X M3:
http://www.m3post.com/forums/showthread.php?t=696371

A lot of the threads say diff, engine and tranny mounts can increase NVH, but not subframe bushes.

I hope that's cleared stuff up for you and you now understand. If not then you can carry on believing that BMW M3s are perfect and that even on a car with twice the torque there's no point going further than M3 bushes. Hopefully once i get my solid bushes in i will post a review, especially on the driveability and NVH, but i can imagine there won't be too much to say.

idnan · 06-13-2015, 04:54 AM

Quote:

Originally Posted by mob17

And about idnan. His case is different. Why? Because he has solid aluminium diff bushes which are very well known to increase NVH. If you have solid diff AND subframe bushes then yes there would be a lot of NVH and it's a good idea to soften one of the two. Which is what idnan is doing i assume.

Yep spot on. Having solid diff bushes causes the whine and a lot of people with both them and solid subframe bushes have noticed it. Almost sounds like a supercharger whining when you're decelerated. I've already snapped an m3 diff heatsink and ruined an m3 subframe so now I've added a diff lockdown brace and a fitted some new OEM bits.

Just FYI. New m5 and m4 both have solidly mounted subframes:

http://f80.bimmerpost.com/forums/sho....php?t=1012291

Fundguy1 · 06-13-2015, 06:49 AM

Remember too each car generation is different. The current M3/M4 come from the factory with solid subframe bushings. The generation of 3 series prior to ours whines like a Jewish grandma with them. If 3 different BMW generations are so different I doubt comparing your experiences with your audI are relevant. I haven't heard of anything but the slightest nvh from one person. Most say nothing. I have heard of noise from changing the Trans and motor mounts. I suspect if you just go solid subframe but you also change motor, trans, and diff bushings to stiffer materials you are going down the nvh trail.
I'm going to give solid a shot. I'm keeping the motor, trans, and LSD ones oem. I do also have an LSD lockdown going on too. This should improve the handling and minimize the hop but still give me my nvh protection.

mob17 · 06-13-2015, 12:46 PM

Fundguy. Thats a good idea about keeping diff bushes oem (or just replace them with new stock ones) and a diff lockdown kit. That may be my next step if the rear is still behaving like it is currently.

Can't wait to get the new stiffer springs and solid subframe bushes on

Will still need an LSD badly but that will have to wait.

Aragorn30d · 06-13-2015, 01:32 PM

The torque things a red herring, becuase between the engine and the road is a big torque multiplier called a transmission. Inside there are gears, and the ratios between a M3 (or any petrol model) and a 35d are significantly different.

This means that while your engine produces much more torque at the crankshaft, because the engine only revs to 4500rpm the gearbox has to "dilute" that torque down to achieve the same road speeds, by using longer gear ratios.

As a result, you'll find torque at the wheels (and thus the forces the rear end is having to deal with) is nowhere near twice what an M3 puts out.

Anyway i will happily conceed that replacing JUST the subframe mounts on their own, may well be perfectly fine and be an overall positive experience, I think the gist of my post was to try to make you aware that going down the road of stiffening everything up leads to a bad place.

You replace the subframe mounts, its still not right, so then the diff gets stiffened up, its still not right, then you end up with polybushed wishbones, stiffened tranny and engine mountings etc etc etc and before you know it the cars ruined and your lying to yourself that its better because its all locked down and "sorted".

Furthermore, reading your first link about alloy mounts, happens also to be full of people saying they've fitted M3 ones and found a huge improvement, much like i suggested above! The rubber parts on your car WILL be worn unless its a super late model thats done no miles, and replacing them with M3 parts WILL make a huge improvement. It might well not be enough for your liking, but dont try to pretend it'll be exactly the same.

As for my own car, its awful, its on 9 year old 140k standard suspension and wallows around like a boat. It'll be getting sorted as and when finances allow over the next while. But im under no illusions that its like that because its got more torque than an M3 (which even a stock 330d does as it happens), its like that because its worn out and knackered.

mob17 · 06-15-2015, 11:26 AM

Quote:

Originally Posted by idnan

Quote:

Originally Posted by mob17

And about idnan. His case is different. Why? Because he has solid aluminium diff bushes which are very well known to increase NVH. If you have solid diff AND subframe bushes then yes there would be a lot of NVH and it's a good idea to soften one of the two. Which is what idnan is doing i assume.

Yep spot on. Having solid diff bushes causes the whine and a lot of people with both them and solid subframe bushes have noticed it. Almost sounds like a supercharger whining when you're decelerated. I've already snapped an m3 diff heatsink and ruined an m3 subframe so now I've added a diff lockdown brace and a fitted some new OEM bits.

Just FYI. New m5 and m4 both have solidly mounted subframes:

http://f80.bimmerpost.com/forums/sho....php?t=1012291

Thanks idnan for the solid rear subframe bushes. Can't wait to get them on

Fundguy1 · 06-20-2015, 06:52 AM

I'm going solid aluminum subframe too. M3 are good but BMW was still too conservative with them to really get the performance out of the car. Now they use solid on M4. If you're going to upgrade your B cups don't go to C cups. Get DD solid aluminum. Worth the extra effort. Otherwise you'll have your c cups and still be wanting more.

06-05-2015, 04:38 PM	#1
acerboo Brigadier General 181 Rep 3,923 Posts Drives: e92 335d lci Join Date: Jul 2008 Location: kent iTrader: (2)	rear powerflex bushes has anyone replaced rear bushes with powerflex
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06-05-2015, 07:13 PM	#2
Jules59 Lieutenant 57 Rep 540 Posts Drives: Still searching ... Join Date: Nov 2010 Location: Wilds of Warwickshire iTrader: (0)	I have some but never got round to changing them - seem really difficult to get at compared to the fronts. __________________ Jules
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06-06-2015, 12:22 PM	#3
acerboo Brigadier General 181 Rep 3,923 Posts Drives: e92 335d lci Join Date: Jul 2008 Location: kent iTrader: (2)	just wondering if theres that much benefit to fitting them
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06-08-2015, 04:09 PM	#4
idnan Lieutenant Colonel 76 Rep 1,518 Posts Drives: Alpine White 335i Join Date: Nov 2010 Location: Birmingham iTrader: (9)	Subframe bushes? Diff bushes? or Rear arm bushes?
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06-08-2015, 04:35 PM	#5
acerboo Brigadier General 181 Rep 3,923 Posts Drives: e92 335d lci Join Date: Jul 2008 Location: kent iTrader: (2)	don't know if some or all need replacing. was thinking just the ones that could affect the steering. I gather some can?
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06-09-2015, 06:24 AM	#6
Icekube Captain 46 Rep 891 Posts Drives: E87 130i Join Date: May 2013 Location: Livingston iTrader: (3)	just fit new OEM bushes. poly's are just overkill, and dont actually work properly.
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06-09-2015, 02:37 PM	#8
Aragorn30d Lieutenant Colonel 175 Rep 1,596 Posts Drives: E90 330d Join Date: Mar 2015 Location: Fife iTrader: (0)	I did solid subframe bushes on my old car and regretted it. Too harsh, too much noise and vibration transmitted into the cabin etc. Go with OEM, M3 ones are probably a decent upgrade without going overkill.
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06-09-2015, 05:04 PM	#10
Aragorn30d Lieutenant Colonel 175 Rep 1,596 Posts Drives: E90 330d Join Date: Mar 2015 Location: Fife iTrader: (0)	They're on my B5 A4 Quattro. For me the solid bushes amplified the small amount of slack that exists in the drivetrain, and turned it into horrible harshness. Make a fast gearchange under power and you get an almighty bang from the rear end as you re-engage the clutch, because everythings so rigidly mounted theres no slack to absorb the shock loadings. I had solid (high density rubber, not aluminium) diff mounts in the car as well which i ended up removing as it was so bad. I guess it depends on what your doing with the car. Yours is a diesel, which lets face it isnt a "sports" car. Its a fast smooth everyday luxury car. Going full on race mode with solid bushings etc will IMO simply ruin what the car is. But maybe you view the car differently to me. If it was a weekender M3 or 335i that you did a lot of track work with then it would be a different story. People often forget, that when BMW built the M3, and reviewers took that car out and kicked its arse, they didnt all start whining about how the suspension was too soggy and it needed rock hard bushes. These cars are universally acclaimed as hitting the nail on the head when it comes to handling and as an all round package. When mine has bits wear out and needs replacements, it'll be getting M3 bits or OEM.
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06-10-2015, 03:30 PM	#12
idnan Lieutenant Colonel 76 Rep 1,518 Posts Drives: Alpine White 335i Join Date: Nov 2010 Location: Birmingham iTrader: (9)	Mob I have some AKG 75d rear subframe bushes with less than 1000 miles on them if you're interested. Same as these ones half way down the page: http://www.akgmotorsport.com/catalog...ion%2FBushings I have aluminium diff bushes, m3 diff and with these the whine was quite loud. I changed to softer Whiteline subframe bushes and they are slightly less harsh and is what I settled on.
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06-12-2015, 09:52 AM	#15
Aragorn30d Lieutenant Colonel 175 Rep 1,596 Posts Drives: E90 330d Join Date: Mar 2015 Location: Fife iTrader: (0)	What your essentially saying, is that BMW M dont know what they're doing, the millions they spent on R&D was pointless and you need to clag in some "upgrade" parts that someone spun up on a lathe in a half hour because they're solid and must be better. Sure, BMW M probably left some performance on the table, but they're producing a high performance road car, which if i'm not mistake is also what you own. If its a dedicated track toy or going even further a race car, then you make changes which seriously detract from the everyday driveability of the car for the last n% of performance. For a road car, you need to find the perfect balance between all the elements. What i'm trying to get across is that its all a very fine line, and what your doing is taking a car full of worn out parts (because after-all, its not new, its driven many thousands of miles over many years) assuming thats representative of how it should be, and thus coming to the conclusion that huge upgrades need to be made because the standard parts are crap. Infact, replacing everything with new standard bits would likely make a huge improvement, and replacing those with the M3 parts would likely make a further improvement again, and you can do all of that with zero impact on drivability because BMW ensured it to be so. The guy your buying the bushes from has already said he's removed them from his car and replaced them with softer ones because it transmitted too much noise into the cabin, but you seem convinced that it'll be rosy.
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06-12-2015, 03:24 PM	#16
mob17 Major General 400 Rep 5,623 Posts Drives: E92 335D Join Date: Mar 2012 Location: East Midlands, UK iTrader: (5)	I disagree with pretty much everything you have said. What are you basing your thoughts on? First hand experience or BMW M3 reviews you read online? You're also basing your opinion on the assumption that my car is stock, it's not, it has more power and over twice the torque than an E92 M3. That's a significant factor! Think about the stresses on the rear subframe. Do you really think M3 bushes, never mine new OEM ones, are designed to handle twice the torque without giving a lot of flex? Even M3 owners on stock M3 power are finding benefits of solid bushes. I tell you what i base my thoughts on. Fellow members on here who are driving higher powered cars than you and I that have upgraded their non-M bushes to solid bushes. M3 owners have also upgraded from M3 to solid. Maybe you should go on M3 cutters or M3post and say people are ruining the everyday drivability by upgrading their M3 bushes. Would love to see the response. I am running over 420bhp and I need to upgrade my subframe bushes. I know my car and i can feel it going sideways at WOT. Hell, i could even feel the rear moving about and skipping before my power upgrade. Maybe if you had a more powerful car you would understand, or maybe your car is powerful enough and you just either drive like a granny everywhere or just don't realise what is happening at the rear, i don’t know. But what i do know it's not due to worn bushes. Remember the OEM non-M bushes, and most of the suspension, was designed for run flats. And about idnan. His case is different. Why? Because he has solid aluminium diff bushes which are very well known to increase NVH. If you have solid diff AND subframe bushes then yes there would be a lot of NVH and it's a good idea to soften one of the two. Which is what idnan is doing i assume. If diff bushes are kept OEM (or slightly stiffened to poly), then the NVH with solid subframe bushes will be very minimal, hard to detect -> this according to people who have actually got solid aluminium bushes on an E9X platform, M and Non-M. Sources here FYI and anyone reading: Fellow 335i driver upgrading to solid aluminium bushes: http://www.e90post.com/forums/showthread.php?t=1125661 Fellow M3 drivers upgrading their M3 subframe bushes to solid aluminium: www.m3post.com/forums/showthread.php?t=926758 Long discussion on various subframe and diff bushes: http://www.e90post.com/forums/showthread.php?t=1055253 Discussion of solid Subframe bushes on E9X M3: http://www.m3post.com/forums/showthread.php?t=696371 A lot of the threads say diff, engine and tranny mounts can increase NVH, but not subframe bushes. I hope that's cleared stuff up for you and you now understand. If not then you can carry on believing that BMW M3s are perfect and that even on a car with twice the torque there's no point going further than M3 bushes. Hopefully once i get my solid bushes in i will post a review, especially on the driveability and NVH, but i can imagine there won't be too much to say. Last edited by mob17; 06-12-2015 at 04:45 PM..
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06-13-2015, 06:49 AM	#18
Fundguy1 Major General 2036 Rep 8,339 Posts Drives: 335 e93 Join Date: Aug 2014 Location: Orlando, fl iTrader: (0)	Remember too each car generation is different. The current M3/M4 come from the factory with solid subframe bushings. The generation of 3 series prior to ours whines like a Jewish grandma with them. If 3 different BMW generations are so different I doubt comparing your experiences with your audI are relevant. I haven't heard of anything but the slightest nvh from one person. Most say nothing. I have heard of noise from changing the Trans and motor mounts. I suspect if you just go solid subframe but you also change motor, trans, and diff bushings to stiffer materials you are going down the nvh trail. I'm going to give solid a shot. I'm keeping the motor, trans, and LSD ones oem. I do also have an LSD lockdown going on too. This should improve the handling and minimize the hop but still give me my nvh protection.
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06-13-2015, 12:46 PM	#19
mob17 Major General 400 Rep 5,623 Posts Drives: E92 335D Join Date: Mar 2012 Location: East Midlands, UK iTrader: (5)	Fundguy. Thats a good idea about keeping diff bushes oem (or just replace them with new stock ones) and a diff lockdown kit. That may be my next step if the rear is still behaving like it is currently. Can't wait to get the new stiffer springs and solid subframe bushes on Will still need an LSD badly but that will have to wait.
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06-13-2015, 01:32 PM	#20
Aragorn30d Lieutenant Colonel 175 Rep 1,596 Posts Drives: E90 330d Join Date: Mar 2015 Location: Fife iTrader: (0)	The torque things a red herring, becuase between the engine and the road is a big torque multiplier called a transmission. Inside there are gears, and the ratios between a M3 (or any petrol model) and a 35d are significantly different. This means that while your engine produces much more torque at the crankshaft, because the engine only revs to 4500rpm the gearbox has to "dilute" that torque down to achieve the same road speeds, by using longer gear ratios. As a result, you'll find torque at the wheels (and thus the forces the rear end is having to deal with) is nowhere near twice what an M3 puts out. Anyway i will happily conceed that replacing JUST the subframe mounts on their own, may well be perfectly fine and be an overall positive experience, I think the gist of my post was to try to make you aware that going down the road of stiffening everything up leads to a bad place. You replace the subframe mounts, its still not right, so then the diff gets stiffened up, its still not right, then you end up with polybushed wishbones, stiffened tranny and engine mountings etc etc etc and before you know it the cars ruined and your lying to yourself that its better because its all locked down and "sorted". Furthermore, reading your first link about alloy mounts, happens also to be full of people saying they've fitted M3 ones and found a huge improvement, much like i suggested above! The rubber parts on your car WILL be worn unless its a super late model thats done no miles, and replacing them with M3 parts WILL make a huge improvement. It might well not be enough for your liking, but dont try to pretend it'll be exactly the same. As for my own car, its awful, its on 9 year old 140k standard suspension and wallows around like a boat. It'll be getting sorted as and when finances allow over the next while. But im under no illusions that its like that because its got more torque than an M3 (which even a stock 330d does as it happens), its like that because its worn out and knackered.
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06-20-2015, 06:52 AM	#22
Fundguy1 Major General 2036 Rep 8,339 Posts Drives: 335 e93 Join Date: Aug 2014 Location: Orlando, fl iTrader: (0)	I'm going solid aluminum subframe too. M3 are good but BMW was still too conservative with them to really get the performance out of the car. Now they use solid on M4. If you're going to upgrade your B cups don't go to C cups. Get DD solid aluminum. Worth the extra effort. Otherwise you'll have your c cups and still be wanting more.
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