BMW F2x F3x Powerflex Subframe Bushing Inserts, Not Recommended 

I'll add another anecdotal data-point, since this is by far the best DIY video around (good job) for installing these bushing inserts, but results clearly differ between different cars and drivers. On my 2017 F22 M240i, with > 450HP (BM3 stage 2 catless), these powerflex bushing inserts (I went with the Black type) have completely transformed the car. This is one of three game-changers for the F22: LSD, Front LCAs, and these subframe inserts. These three modification have made the biggest impact on how the car feels. Tyres and the LSD sort out the traction, M3/4 LCAs and tension struts (sort of) sort the steering. I had been resigned towards making the big purchase of coilovers in order to try and fix how the car handles and connects to the road, especially under maximum tractive force, where these soft semi-M cars get horribly squirrily. But having put these inserts in this morning, I am reconsidering whether coilovers are even needed. The car feels planted. Certainly I can postpone that installation for a while longer. As far as NVH goes, in my case, I can't hear or feel any difference. The subjective impression is that everything is smoother since things aren't wriggling so much. If anything it's quieter, my subframe used to sing at a high pitch, that seems less now.

FINALLY a before and after and not just another install vid... Thanks

the whole F-series world: "these inserts are a must!!"

I installed the Powerflex black Bushing inserts in my F22 yesterday. Video was very Helpful. Ive noticed now that yes the ride is bumpier, comparable with stiffer springs but the front to back movement of the rear axle improved a lot. When the Transmission now shifts up the rear is no longer bouncing the car like a rubber spring, the shift jerk directly transfers in the chassis. It is very noticable in a positive way. Also when cornering it sits firm, not this kind of spring feeling like the rear axle is connected to the chassis with springs in a strange way. Regarding ride comfort: I expected a lot worse, it is ok for me even with bad pavement, this might be because of the shorter wheelbase of the F22 chassis i own... so For guys that are Planning to do this mod, be aware of the drawbacks but if you still wand to install them go straight for the black ones. I can Imagine the yellow ones might decrease comfort without gaining a lot of stability so they are not the best choice

Greatly appreciate this video...! I have read for many many years that going to firmer bushings often doesn't yield useful benefits for a street car and can even make a vehicle less comfortable and less enjoyable. I was looking at these for my X5, which already has a fairly firm ride and I could appreciate a more connected feel and better handling, but not at the risk of an even harsher ride; especially considering that it is pretty awesome stock. For once, a video where someone does a mod and the results aren't that great and you weren't afraid to admit it. Thank you for this.

I have got these inserts in my E92 330d. I fitted them after using a go pro to see what the subframe was doing before and after fitting them when i was driving in a spirited manner. The movement of the subframe definitely reduced with the inserts, confirmed by how the car felt. My car is a lot older so the original bushings are more worn so the difference will be more noticable i guess. The downside is they've created a drone at a certain RPM under load, something i've not found anybody else complaining about so i don't know why i'm suffering it. Anyway, because of that i'm shying away from replacing the bushings with polybushes and going to use stock M3 items which are a direct fit i believe.

For anyone doing this mod, I highly recommend just doing the entire bushing instead of inserts. I just did this mod with ECS Tuning brand 95a poly diff & subframe bushings and the results are amazing. No added harshness (surprisingly less harsh than my previous OEM bushings) no vibration either but I do have more diff noise than usual. & I drive on shitty Texas roads

Well done for giving an honest review of these inserts and not being a sheep. I'm not quite sure what makes people believe that pieces of polyurethane or teflon composits are going to suddenly change the car in a phenomenal way.. bmw spends billions on engineering literally.. these things are cheap as chips to produce if they work surely we would see them somewhere in the motorsport line up... people with F3x/32 shouldn't even consider these due the longer wheel base and lower natural frequency sorting out a ton of the inherent waywardnes of the F20/21. In short Fit KWs or Bilsteins and run a good compound tyre

Thanks for your honest review ! ...usually everybody is just mentioning the positive things of their mods

These inserts are not meant to make the ride nicer. They are to stop the play that oem ones have for more track orientated set ups. The reason they dont feel nice is there is no play in the bushings anymore for that comfort. Its like adding coilovers and complaining the ride is too hard now. It has its benefits but you will sacrifice comfort

I have installed these on my F20 M140 and they actually improved the turn-in significantly. No noise increase, just a bit more harshness over potholes etc

Problem is, the OE bushing deflection is connected to rear subframe cracks on these cars. The lower subframe slams into the upper as the bushings wear out. People say these PE inserts (or the complete PE bushing kits) protect against the damage of metal to metal collision and further better distribute the stresses of the subframe as the OE bushings each only have the 2 feeble rubber ears as you see in your video. The inserts have depressions molded into them where the 2 OE rubber bushing ears fit into them.

I did these inserts in my e92 and noticed a improvement of roughly 25%. I also did M control arms all around which helped even more. I now want to ditch the inserts for Solid subframe bushings. They do not add any NVH this is a myth. It is the the trans and diff bushings that cause more nvh. The e92 M3 crt or whatever its called came with solid SB. Also the f80 m3/m4 now use solid SB

I have done inserts on a e92 335i and had great results. I would say the amount of NHV added is comparable to the M3 tension arms I did previously. Now planning on doing it on our wagon. I'm curious what tires were you running during the test.

That freeway looks insanely bad. Must be in CA - lol. Thanks for the honest review!

Interesting. I used your diy tutorial when I did my sway bar (btw in that video you installed the hr swaybar but in this one it seems you have the kc design installed?) and ince I had the subframe already lowered, I also switched the bushings to aluminum ones from millway. I think it's the best thing you could do to the rear end of an f30. You get a much bitter feel for the car and I actually like the stiffness it adds.

I have a 135i and went with the 034 Motorsport aluminum set. Amazing. I'd say as good as the M3 bushing set. Did you try them out around corners and when applying power?

Hi mate ! I also had these inserts on my F36 440ix. Same conclusion as you, they are useless ! I bought Superpro complete rear subframe bushings, will install them with my set of other modifications once I return to the shop. Take care !

When ever I installed a urethane bushings they always throw off the suspension frequency and makes the car bouncy is heck. I put the 034 Motorsports ones in my B8 A4 and loved them. The rear became more planted and sure footed. I just bought the 034 ones for my F30.

Nice honest review :)

polyurethane is not for ride quality is for performance under stress. i noticed it wasnt for you at first sight

Did you get an alignment after installing the inserts? I'm pretty sure your alignment would be off if you didn't.

They say it mess up the riders feeling completely

I want to get more stability in the rear when moving at high speeds, what all would i need besides rear subframe bushings?

I'm running a turbo upgrade so making 625whp ish and it really has made the rear feel weak and spongy. It seems to load up and rebound. I need to do something but I'm not sure this is the answer. Did you produce an installation video?

Why would you assume, that taking something with soft rubber bushings and making them solid wouldn’t make the car ride like dog shit.

Why skip this mod? Not enough of a difference? Have you seen the diff mounts they offer as well?

Do you recommend?

Do you have any problems whit DEF systems? Some people saying lot of problems whit diesel motor

So you dont need to drop subframe to do bushings?

Wow what a shitty road

It won’t make a “difference” you want on a F or “new” car. It wasn’t meant for a replacement and Sunday drive… sorry buddy u rolling on da road. Make a”street” vid.