B12 Pro Kit Advice

[YoungFireOldFlame]

Hi,

B12 Pro Kit fitted to my E87 120d (M47D2) at the same time had front and rear 1M/M3 tension struts & LCAs, top mounts, springs pads, rear Powerflex yellow upper mount bush, BMW rear bottom mounts, x4 new ARB drop-links, Powerflex purple ARB bushes, wheel bearings, SPL adjustable tie rods, Powerflex rear subframe inserts and alignment at AMD tuning. I have PS5 225/40 R18 front and 245/35 R18 rear. I've had them on 6 months and summers here I like go for a drive but finding it a bit harsh on pot-holey A/B roads. I like the damping/roll control as it always spot on even with the stage 2 (200+BHP/325lb-ft + xHP stage 2) pressing on but over pot-holes and the like it's uncomfortable, smooth surface and it's fine. Apart from A/B roads, I do the novice track-day at Brands but treat it as B road rather than an audition for BTCC, so not really looking for track focussed setup. Previously I had Eibach Pros + Koni FSDs but wanted somthing a bit more sporty...

Previously I had a Boxster 987.2 with PASM & DSC Sport V1 PASM controller with 19" Sport Design alloys PS2 N rated tyres, so I know how a sports car should feel/ride. Not sure where to go...


Thanks
Hayden

[helix403]

The E8x/E9x platforms suffer from poor ride quality generally. The B12 kit gives a marginal improvement in ride quality. The Birds suspension kit gives a greater improvement in ride quantity.
Other spring/damper kits may give a superior ride quality but I’ve not tried them on the E8x/9x chassis.

Edited by helix403 on Saturday 17th May 23:30

[YoungFireOldFlame]

helix403 said:

The E8x/E9x platforms suffer from poor ride quality generally. The B12 kit gives a marginal improvement in ride quality. The Birds suspension kit gives a greater improvement in ride quantity.
Other spring/damper kits may give a superior ride quality but I’ve not tried them on the E8x/9x chassis.

Edited by helix403 on Saturday 17th May 23:30

It sure is out of the box. Will look at the Birds kits, I take it's night and day difference to the B12?

[danb79]

I've got the B14s on my 130i - part of a full suspension overhaul (every arm/bush/link etc) alongside Whiteline rear subframe bush inserts and the car drives superbly; not stupidly firm and takes the rough, local rural roads here in Lancashire brilliantly

All fitted and set up perfectly by my pals that have Grinspeed up this way

I have been out in cars with the B12 kit and always found them to be superb when being pushed hard; but normal driving on normal roads etc; just too firm & bouncy

I've also been out in an F30 & an E92 that had the Birds kit on and wasn't that wowed; neither were the owners (one inherited the suspension at 9 months old; the other bought it brand new)

I know they have their fanbase and they are good at what they do; but for me I don't think they're all that; also very expensive for what are just re-valved shocks with springs (plus you've got to add in the costs for new top mounts all round, spring perches etc - that's if you'e going to replace all that, which IMO makes sense whilst it's all out)

[gareth h]

YoungFireOldFlame said:

It sure is out of the box. Will look at the Birds kits, I take it's night and day difference to the B12?

I had their kit on my old F31, I wouldn’t bother again, and certainly wouldn’t let them install it!

[Jamescrs]

Maybe look at a set of proper adjustable coilovers with adjustable height and damping to give you more options. you can then always stiffen the damping for track days

[YoungFireOldFlame]

So I see it's not a slam dunk for the Birds setup. I'm thinking may be a bit more sidewall chubbiness could be the cure. I'm currently on 225/40 R18 XL may be switching up to 45 or 50 profile will help taking the edge off...

[YoungFireOldFlame]

Jamescrs said:

Maybe look at a set of proper adjustable coilovers with adjustable height and damping to give you more options. you can then always stiffen the damping for track days

I'd rather buy something that has been setup, rather something that needs to configured up. I haven't got that knowledge or the equipment to work with to set'em up. I definitely don't have the cash to hire a suspension guru...

I like the B12 Pro Kit in terms of damping just need the tyres to take some of the shock/sting to take out of the ride on pot-holes. I used have a 3 series on 16" with non XL tyres and that used ride beautifully

[danb79]

YoungFireOldFlame said:

So I see it's not a slam dunk for the Birds setup. I'm thinking may be a bit more sidewall chubbiness could be the cure. I'm currently on 225/40 R18 XL may be switching up to 45 or 50 profile will help taking the edge off...

Dropping to 17s would be a good way to do it

There's quite a few folk on BabyBMW forums that run the 17" OZ Leggera's with 225/45/17s (or 215/50/17s) - something like that and they find it to be an excellent ride (lightweight wheels, they make a lot of difference; something I've noticed massively with my Protrack One alloys on my 130i)

I'll probably be going for a set of Style 304s for my winters; they're 17s that fit over the 340mm Brembo brakes and will run all-season tyres for over winter (probably Goodyear Vector Gen3s)

Personally I'd try that route first before you start swapping out suspension

I don't find my 130i too firm at all; it's been very well dialled in when it was being set up; but I do think the lightweight wheels and suspension overhaul has worked wonders for the B14s and vice-versa

[danb79]

YoungFireOldFlame said:

Jamescrs said:

Maybe look at a set of proper adjustable coilovers with adjustable height and damping to give you more options. you can then always stiffen the damping for track days

I'd rather buy something that has been setup, rather something that needs to configured up. I haven't got that knowledge or the equipment to work with to set'em up. I definitely don't have the cash to hire a suspension guru...

I like the B12 Pro Kit in terms of damping just need the tyres to take some of the shock/sting to take out of the ride on pot-holes. I used have a 3 series on 16" with non XL tyres and that used ride beautifully

This is why I went for the B14s - so the ride height could be dialled in properly and the rest is nigh on OEM factory. All new OEM BMW top mounts used all round; the fronts had the locating pin removed (just unscrewed) to allow my pals to dial in the camber (not silly aggressive, but right for the car and for a fast road set up) and that's it...

I'll probably never change the right height as there's no need; it clears speed humps without issue

[gareth h]

YoungFireOldFlame said:

So I see it's not a slam dunk for the Birds setup. I'm thinking may be a bit more sidewall chubbiness could be the cure. I'm currently on 225/40 R18 XL may be switching up to 45 or 50 profile will help taking the edge off...

Are you still on runflats?

[gareth h]

gareth h said:

YoungFireOldFlame said:

So I see it's not a slam dunk for the Birds setup. I'm thinking may be a bit more sidewall chubbiness could be the cure. I'm currently on 225/40 R18 XL may be switching up to 45 or 50 profile will help taking the edge off...

Are you still on runflats?

Sorry, just read your original post, you’re already on decent tyres, years back I had a 123d coupe, which came on 18s which were harsh, I changed to 17s, it was much more composed on poor roads.

[rottenegg]

YoungFireOldFlame said:

helix403 said:

The E8x/E9x platforms suffer from poor ride quality generally. The B12 kit gives a marginal improvement in ride quality. The Birds suspension kit gives a greater improvement in ride quantity.
Other spring/damper kits may give a superior ride quality but I’ve not tried them on the E8x/9x chassis.

Edited by helix403 on Saturday 17th May 23:30

It sure is out of the box. Will look at the Birds kits, I take it's night and day difference to the B12?

Nope. It's the B12 kit but the B8s are sprayed black. Yeah they had Bilstein UK adjust the compression valving a bit, but essentially it's the same thing.

I have the B12 kit on my F30 330d and I find the ride quality very good. Sure you feel everything, but the way it deals with bumps and undulations is superior to twin tube dampers. Nothing rides well in pot holes except air ride cars with huge profile tyres. Even stock M Sport suspension bottoms out over pot holes in a loud and crashy way. Just avoid them!

You've also got poly and ball joint arms, which exacerbates NVH.

[helix403]

rottenegg said:

Nope. It's the B12 kit but the B8s are sprayed black. Yeah they had Bilstein UK adjust the compression valving a bit, but essentially it's the same thing.

I have the B12 kit on my F30 330d and I find the ride quality very good. Sure you feel everything, but the way it deals with bumps and undulations is superior to twin tube dampers. Nothing rides well in pot holes except air ride cars with huge profile tyres. Even stock M Sport suspension bottoms out over pot holes in a loud and crashy way. Just avoid them!

You've also got poly and ball joint arms, which exacerbates NVH.

The Birds kit has unique springs. The dampers remain yellow in E8/9x applications.

[swanny71]

Not long after getting my dearly departed 130i, I tried both the B12 and the Birds set up on two different cars (albeit about a month apart). B12 was way too crashy and I didn’t think the Birds set up was worth the significant cost. In the end I settled on B4 dampers and Eibach Pro springs and was very happy with that set up for 100k miles.

Installed the B12 kit on my current M135i and it’s a fantastic improvement over stock and excellent value for money (5years ago).

Personal experience suggests the B12 kit is much better resolved on the F chassis than it is on the E chassis. Birds just too expensive for my use case.

[danb79]

swanny71 said:

Not long after getting my dearly departed 130i, I tried both the B12 and the Birds set up on two different cars (albeit about a month apart). B12 was way too crashy and I didn’t think the Birds set up was worth the significant cost. In the end I settled on B4 dampers and Eibach Pro springs and was very happy with that set up for 100k miles.

Installed the B12 kit on my current M135i and it’s a fantastic improvement over stock and excellent value for money (5years ago).

Personal experience suggests the B12 kit is much better resolved on the F chassis than it is on the E chassis. Birds just too expensive for my use case.

My 130i came on B4s with Eibach pro kit springs and it drove really well; but it wasn't right and that's why I went for the B14s as part of the overhaul

Personally I think Birds is more hype than anything else; for nearly the same money you could get KW V2s, ST XTA's and Bilstein B16s and have the car dialled in much better

[YoungFireOldFlame]

I have not found it B12 Pro Kit to be crashy, more I would say not comfortable over rough tarmac. To be honest that comfort really came from moving from XL tyres to non XL tyres on previous E90 320d. I think a soft side wall tyre would take the shock/energy by deforming to work in harmony with the road.

I’m also wondering if my Pro kit front springs have sagged, had them on since 2017, initially with SE bumpstops, then BMW Performance suspension (shorter) bumpstops. Once the car is back from the body shop I’ll put a few photos up.

[YoungFireOldFlame]

This is the front driver's tyre-arch gap. I think the car sits lower than Eibach Pro height?



My finger has to be pointed up to get in otherwise the tyre would block it...



I like the stance though...

[danb79]

YoungFireOldFlame said:

This is the front driver's tyre-arch gap. I think the car sits lower than Eibach Pro height?



My finger has to be pointed up to get in otherwise the tyre would block it...



I like the stance though...

This is mine on Bilstein B4/Eibach pro kit suspension before I replaced it all:



Yours looks a touch lower; so not sure if the shocks or springs have had it maybe?

My wheels were on 12mm spacers all round too with 235 rear and 225 40 front Michelin CC2s

[YoungFireOldFlame]

danb79 said:

This is mine on Bilstein B4/Eibach pro kit suspension before I replaced it all:



Yours looks a touch lower; so not sure if the shocks or springs have had it maybe?

My wheels were on 12mm spacers all round too with 235 rear and 225 40 front Michelin CC2s

I think they have probably shrunk when I had the soft SE bumpstops + Eibach Pros + FSDs. Springs are 9 years old and the dampers 6 months old...

Edited by YoungFireOldFlame on Saturday 24th May 21:05