[Hbyton]

Hi everyone,

Having recently purchased a 335D X drive, like many I have found the standard suspension setup to be poor which does not inspire confidence during cornering or travelling at high speeds. I’ve spent a good few days looking at similar threads on the forums/generally going as much research as possible in to potential upgrades.

I would like to replace the Shocks and dampers and have narrowed it down to two options.

1. Birds B3 kit
2. ACS springs with B4 Dampers

Whilst I am looking to improve the handling, it is important to me that the ride is also improved (the bouncing over rough roads leads to borderline sea sickness!)

Any advice/input would be appreciated- Specifically on option 2 as this is what I am currently leaning towards and will work out cheaper.

As for the tyres, they are Eagle F1 run flats, I will swap them out for non run flats when they are worn.

Thanks

[rlesko]

There is a thread floating around here with much more detailed information about suspension set ups, damper dynos, spring rates, etc.

ACS seem to be a 'waste' of money - they are rebranded Eibach springs AFAIK.

Don't try to compensate for the undersized F30 sway bar with stiff suspension. Its expensive to install a new sway bar, but you probably need that more than anything else.

[Ennoch]

Originally Posted by rlesko

ACS seem to be a 'waste' of money - they are rebranded Eibach springs AFAIK.

They're made by Eibach, not re-branded. Many companies get Eibach to make springs to their own specs, and Eibach also make their own springs with their own logo on them. What you want from your spring will decide which option suits you best. Eibach made many various Impreza springs over the years for both Subaru themselves, Prodrive, and Peter Cambridge (who sorted the suspension on the P1 and RB320 versions), as well as their own. The ones they made for others were all better than their own branded ones which didn't have the same degree of testing and tweaking to get ride, balance, handling and comfort balanced etc. For some the Eibach's will be perfect but don't think the ACS are just the same spring with a different logo and an increased price.

[cfm56d7b]

Hbyton, I suggest to explore Koni Special Active shocks and ACS springs (which are made by Eibach). Please see this thread:

https://f30.bimmerpost.com/forums/sh....php?t=1728673

PS. A lot of credit is due to johnung for sharing his experience with Koni SA shocks and Eibach Pro springs.

[danb1979]

Originally Posted by Hbyton

Hi everyone,

Having recently purchased a 335D X drive, like many I have found the standard suspension setup to be poor which does not inspire confidence during cornering or travelling at high speeds. I’ve spent a good few days looking at similar threads on the forums/generally going as much research as possible in to potential upgrades.

I would like to replace the Shocks and dampers and have narrowed it down to two options.

1. Birds B3 kit
2. ACS springs with B4 Dampers

Whilst I am looking to improve the handling, it is important to me that the ride is also improved (the bouncing over rough roads leads to borderline sea sickness!)

Any advice/input would be appreciated- Specifically on option 2 as this is what I am currently leaning towards and will work out cheaper.

As for the tyres, they are Eagle F1 run flats, I will swap them out for non run flats when they are worn.

Thanks

Welcome on board; might be worth asking in the UK section as you'll get good coverage from fellow owners here in Blighty etc and those that know how our roads are too

https://f30.bimmerpost.com/forums/fo...412&order=desc

I myself am soon to refresh the suspension on my F31 touring and will be fitting all new main arms, links with Lemforder stuff and I'm still to decide between KW Street Comfort and Bilstein B16 coilovers

I'd researched the Birds offerings, but I want to lower the car a bit also (not silly low at all); but Birds is a fixed set up and that's no good. Apparently it'll lower the car but not a lot and you still end up with the BMW 'rake'

FWIW I run 18x8 OEM BMW 405Ms all round on Goodyear Assym6 tyres and they're superb, so much better then RFTs and the car handles/drives better with an all round better turn in feel on the straight set wheels

Keep us posted as to how you get on