[FaRKle!]

Originally Posted by madmax240

Following this thread as I'm chewing through tires just commuting.


For the price, getting coil overs is probably where I'll end up. but I saw these Power Flex bushes online.


https://www.litchfieldmotors.com/sho...road-series-2/


https://www.bimmerworld.com/Suspensi...F34-F36_2.html


https://www.bimmerworld.com/Suspensi...3-F34-F36.html


All seem to be adjustable and for different parts of the suspension. any advice on the best way to go with these? Also, anyone with long term feedback on adjustable bushes? i.e. 12 months or more of use, how are they holding up???
thanks

I'd be a bit wary of camber bushings where the polyurethane flanges that are supposed to keep the arm from rocking laterally aren't supported by a more rigid material. I posted in another thread how I inspected a set of SuperPros with a similar design starting to fail. I could rock the wheel fore and aft in the wheel well because the bushing was failing.

Originally Posted by FaRKle!

4) The main bushing is cylindrical. These shouldn't have the same failure mode as the SuperPro bushings. I actually inspected a failed SuperPro bushing this weekend. The flange that's supposed to prevent forward/rearward deflection/travel on the SuperPro bushing weakened and allowed the arm to rock laterally, vs only pivoting around the main cylinder. KMAC's design shouldn't fail this way for two reasons. The first is the metal inner bushing/cylinder is much larger. Since it's rigid, it allows less deflection (the metal inner cylinder in SuperPro's bushing is tiny). Secondly, KMAC uses metal end washer/caps that encapsulate the PU sleeves, so the PU is supported by metal and not supporting the lateral load all on its own.

[madmax240]

Originally Posted by FaRKle!

I'd be a bit wary of camber bushings where the polyurethane flanges that are supposed to keep the arm from rocking laterally aren't supported by a more rigid material. I posted in another thread how I inspected a set of SuperPros with a similar design starting to fail. I could rock the wheel fore and aft in the wheel well because the bushing was failing.

thanks, I've been reading the other threads and I'll check the other brands.




I'm not one to be the beta tester for any products.

[Pbdeed]

Originally Posted by Sypher

There really isn't much information out there for the adjustable bushes for our cars. I'll update on the durability and how well they stay after a while (might need a reminder). As for Superpro vs Powerflex, I chose Superpro because honestly, I've never heard of Powerflex until now. I probably would've went with powerflex since they advertise to be stiffer than stock... but then again, I just tried looking and it's pretty hard to find a Canadian/US pricing for the ones we need without having to call shops.

Any feedback about this?

[Pbdeed]

Originally Posted by FaRKle!

I'd be a bit wary of camber bushings where the polyurethane flanges that are supposed to keep the arm from rocking laterally aren't supported by a more rigid material. I posted in another thread how I inspected a set of SuperPros with a similar design starting to fail. I could rock the wheel fore and aft in the wheel well because the bushing was failing.

What about the powerflex Black series? They are stiffer.

[Freddie_Rome]

Originally Posted by x233

I don't think this has ever been mentioned before but it may be useful.

A lot of folks complain about excessive wear of the outside of the front tires which is due to the lack on negative camber on the stock car that cannot be adjusted.
As a result those looking to change that either
a) use m3/m4 front LCAs which gives a fixed increase of about 1º of negative camber but also moves the front wheel forward which may result in clearance issues, and
b) use third-party camber plates, which is a way to go if track is your thing, but that results in NVH and some loss of comfort, and wheel alignment may be more complicated than some would be willing to accept.

There is, though, a different way to get both a moderate increase in negative camber and making it adjustable using OEM parts.

First, our cars can be fitted with 3 different OEM steering knuckles.



In addition to what our cars come with from factory there are 2 optional OEM steering knuckles that can give us either a fixed -30 min of camber or +30 min of camber. We, of course, are interested in the ones that make camber half a degree more negative.

For M235i the part numbers are:
31216853651 (L)
31216853652 (R)

For M235iX the part numbers are:
31216856535 (L)
31216856536 (R)

Essentially, these are identical to the stock parts except for the slightly displaced connection points for LCAs and tension struts. These are used by BMW to correct some camber issues in certain situations but in our case they can add 0.5º of negative camber to whatever it was before without moving the wheel forward/ changing caster.

These can be purchased from BMW and installed by the dealer.

Second, in addition to the upgraded OEM steering knuckles we can swap the inner bushings of the lower control arms for adjustable polyurethane things that will give us an on-car adjustability in the range of 1º in addition to the increased by 0.5º negative camber.



Currently, there are SuperPro bushings that can be fitted on the whole range of F2x and F3x cars including M235i and M235iX.

The 2 steps should give us an adjustability of about 1º and a total of up to 1º more negative camber.

In my case the car is lowered on Eibach springs and has about -1.15 front camber. Upgrading the steering knuckles alone is going to make it up to -1.45º, making it adjustable this way I could get it up to -2.15º. (probably more than enough for DD).

Sounds good to me. Especially since this doesn't involve any loss of comfort, NVH, etc., and doesn't make wheel alignment any more complicated than it has to be.

I'm not saying this is the best possible way to do it, and there's a price tag that comes with the upgrade, but because I do not track this car and, therefore, don't need more range of adjustability that only camber plates can provide this is what I am going to do.


PS: it's also possible to adjust caster using SuperPro poly for the front tension struts but that would be a different story.

Hello, I would like to install steering knuckles, 31216853651 (L) and 31216853652 (R), on my F20, to get some negative camber.
Do you know if this operation is plug&play? Can I use pre-existing screws, nuts and bolts? Thank you!

[x233]

Originally Posted by Freddie_Rome

Hello, I would like to install steering knuckles, 31216853651 (L) and 31216853652 (R), on my F20, to get some negative camber.
Do you know if this operation is plug&play? Can I use pre-existing screws, nuts and bolts? Thank you!

First, look for the part numbers for what you already have on your car. Part numbers for swivel bearings can be found if you look at the swivel bearings from inside, you may need to clean that surface first. Just to make sure you don't already have the parts in question installed on your car.

It is plug&play since these are OEM parts. I am fairly certain BMW recommends replacing the nuts and bolts. (but I also think you can probably reuse them)

[Freddie_Rome]

Originally Posted by x233

First, look for the part numbers for what you already have on your car. Part numbers for swivel bearings can be found if you look at the swivel bearings from inside, you may need to clean that surface first. Just to make sure you don't already have the parts in question installed on your car.

It is plug&play since these are OEM parts. I am fairly certain BMW recommends replacing the nuts and bolts. (but I also think you can probably reuse them)

Thank you, I'll check that, but usually only M140i get the "negative" one from factory. Standard F20 is 0° on the front axle...
My goal is to get at least -1° of camber: 0,5+ lowering.

[Freddie_Rome]

Do you know what is torque spec of the wheel bearing bolt? (N. 6)
Thank you.

[FaRKle!]

Originally Posted by Freddie_Rome

Do you know what is torque spec of the wheel bearing bolt? (N. 6)
Thank you.

80Nm + 90deg (new bolt)_