[tylerhart_21]

I sent an email to Alpina a few days ago to find out how they set up the B3 suspension. The answer I got "It is not possible to convert an excisting BMW into a B3." Turns out you can with just some research.

Sway Bars:
Front: 26.5 mm (M-sport)
Rear: 13mm (Standard)
"They say a bespoke rear sway bar but the rear sway bar bushing hole is 13mm"

Springs:
M sport

Struts:
M sport (e92 or e93)
Standard (e90)

Rear Subframe:
335d subframe and bushings

Wheels:
Front: 19 inches 245/35
(D3 19 inches 235/35)
Rear: 19 inches 265/30

Chassis reinforcement:
Unknown?

If you want to turn the turn-up version of the b3 the gt3. It's the same principle as the b3.

Sway Bars:
Front: 26.5 mm (M-sport)
Rear: 18 mm

Springs:
M sport
(Front has a secondary spring) "Not sure what that means"

Struts:
M sport

Rear Subframe and Bushings:
335d Subframe and bushings

Wheels:
Front: 19 inches 245/35
Rear 19 inches 265/35

Chassis reinforcement:
Front m3 strut tower brace

Personal Questions:
Is the secondary spring a bump stop or something totally different?

Why use the 335d subframe and bushing besides the ability to handle more torque?

[The Nightman]

Secondary spring should be the bump stop. It looks like all Alpina E90 models use the 335xi bump stop (#31336783481)

335d subframe should be the same as other non-M models with the exception of better (solid?) bushings. They probably just used the entire pre-assembled subframe instead of swapping bushings. The same can be achieved with inserts or solid bushings I assume.

The Alpina parts catalogue is interesting to browse through: https://www.alpina-automobiles.com/f...x_Englisch.pdf

I found it interesting that there appears to be Alpina specific strut mounts

[tylerhart_21]

Originally Posted by Guy Fieri

Secondary spring should be the bump stop. It looks like all Alpina E90 models use the 335xi bump stop (#31336783481)

335d subframe should be the same as other non-M models with the exception of better (solid?) bushings. They probably just used the entire pre-assembled subframe instead of swapping bushings. The same can be achieved with inserts or solid bushings I assume.

The Alpina parts catalogue is interesting to browse through: https://www.alpina-automobiles.com/f...x_Englisch.pdf

I found it interesting that there appears to be Alpina specific strut mounts

My front struts are leaking and it's time to replace them. In your own opinion is it worth the trouble of trying to get the strut mounts. While I am in there I am will add the Dinan camber plate (That should act like my spacer).

[The Nightman]

The Alpina specific strut mounts? Probably not. I assume the mix of Alpina and BMW parts is designed as a package to yield a specific wheel rate or frequency that Alpina wants.

[Maxmax73]

Doesn't look like much of a difference/ improvement over "sport" bmw suspension. What's the intention of pursuing this upgrade?

[tylerhart_21]

Originally Posted by Maxmax73

Doesn't look like much of a difference/ improvement over "sport" bmw suspension. What's the intention of pursuing this upgrade?

Disclaimer: I haven't done this setup, everything is based on assumption.

I would say it's the best bang for your buck when it comes to street driving and spirited driving. (Assuming you have the m sport suspension) The front sway bar you can get for around 200 dollars. The rear subframe bushings is up to you. From what I have read I would just go with solid rear bushings. You can feel the rear more and no added nvm (noise and vibration). Price for the subframe bushings are from 200-400, plus if you diy the bushing or getting a shop to do it for you.

There are more options out there like Dinan, M Performance, H&R, K&W etc. I would just start with step one and then work my way up. So you don't buy a whole set-up and hate it.

[Maxmax73]

Originally Posted by tylerhart_21

Disclaimer: I haven't done this setup, everything is based on assumption.

I would say it's the best bang for your buck when it comes to street driving and spirited driving. (Assuming you have the m sport suspension) The front sway bar you can get for around 200 dollars. The rear subframe bushings is up to you. From what I have read I would just go with solid rear bushings. You can feel the rear more and no added nvm (noise and vibration). Price for the subframe bushings are from 200-400, plus if you diy the bushing or getting a shop to do it for you.

There are more options out there like Dinan, M Performance, H&R, K&W etc. I would just start with step one and then work my way up. So you don't buy a whole set-up and hate it.

No, I was just curious why one would try doing something that isn't going to be much different ("alpina" setup) in terms of improvement over sport suspension, that's all)) Front sway bar for $200? My car already has it, doesn't it?

[tylerhart_21]

I believe the front sway bar is from a e90/e92 m3 or m1. I may be wrong but the stock m sport sway bar is 22 mm or around that size.

[tylerhart_21]

It’s been some time, but I may have a hit on the front shock mounts for the Alpina. Part #31 33 136 comes up as a z4 part. So I believe that could solve the missing piece. Plus most people like having the z4 shock mounts over the original.

[neilvan]

Interesting; I did some digging on the 335d rear subframe.

The Autos were the same as the rear but manual diesels got a stiffer rear subframe bushing (hence the diff part numbers); and they share this with the 2014+ E84 X1s and the F20 N20/B48 cars (33316769376). Looks like solid rubber so could be an upgrade to match with the E90 M3 ones.

Funny enough the F30 N55/B58 cars got a different bushing that looks less solid? (33316880637)

[The Nightman]

Originally Posted by neilvan

Interesting; I did some digging on the 335d rear subframe.

The Autos were the same as the rear but manual diesels got a stiffer rear subframe bushing (hence the diff part numbers); and they share this with the 2014+ E84 X1s and the F20 N20/B48 cars (33316769376). Looks like solid rubber so could be an upgrade to match with the E90 M3 ones.

Funny enough the F30 N55/B58 cars got a different bushing that looks less solid? (33316880637)

Those part numbers appear to be the differential mount bushings?

The diesel specific rear subframe bushings are 33316768645. They're also used on all E91 models: https://www.realoem.com/bmw/enUS/partxref?q=33316768645

[neilvan]

good catch, yes I was looking at the diff bushings for the upgraded big rear one; since you can get the M3 ones for the rest.

Makes sense for the diesels with the extra torque but the E91 surprises me

[mattanderson]

Originally Posted by tylerhart_21

It’s been some time, but I may have a hit on the front shock mounts for the Alpina. Part #31 33 136 comes up as a z4 part. So I believe that could solve the missing piece. Plus most people like having the z4 shock mounts over the original.

Interesting that there are both #31 33 135 and #31 33 136 for left and right, though.

Alpina E9x Parts Catalog

Curious where you see it come up as a Z4 part number?

[tylerhart_21]

Originally Posted by mattanderson

Interesting that there are both #31 33 135 and #31 33 136 for left and right, though.

Alpina E9x Parts Catalog

Curious where you see it come up as a Z4 part number?

The #31 33 135 doesn’t come up as a right match with the oem part number.
https://www.schmiedmann.com/en/produ...1-33-1-135-580
Looking at this post on the set up on the Alpina, they say the front is 10 mm lower but the rear is the same height. The z4 shock mounts will lower the car 10mm.
https://www.e90post.com/forums/showthread.php?t=1332583
But the z4 shocks mounts came from the idea that Alpina uses the the m-sport springs. However this could be false and like the post says a special part.

[tylerhart_21]

After looking around a little today, the idea of the 335d subframe bushing being different is false. The rubber and the center bushing is made the same as the 335i ones. Why is it just a different subframe I got no idea.