[McBeemer]

I have ACS sports suspension installed on my car (F31 335d) The ACS springs were fitted from new (well, with 18 miles on clock !) & the ACS dampers fitted at 29k miles. One of the rear dampers is now leaking (I now have 112k on the clock) & although the car still feels decent, I'm sure the car would benefit from new shocks & dampers. I have enjoyed the ACS sports suspension on the car & would like to keep the comfort level that I have at the moment.
I cannot refurb the existing dampers to use on the car as that would take too long & ACS are not available anymore.
I am seriously considering the Birds kit, but would like to know that the comfort level is similar to the ACS setup. If it was ever so slightly firmer, that would be alright.
Anyone else using the Birds kit? especially up in Scotland

cheers, Mark

[SEF]

I’ll be following with interest, my f31 335d has now hit 80k miles on original adaptive dampers and ACS springs fitted since almost new in 2016.
It would definitely benefit from a spring and damper refresh, but am unsure what to go for.
I have considered changing to an M340d but they just seem so expensive, even at 3-4 yrs old, so may spend a bit on my existing car and keep it another few years.

[V330d]

Originally Posted by McBeemer

I have ACS sports suspension installed on my car (F31 335d) The ACS springs were fitted from new (well, with 18 miles on clock !) & the ACS dampers fitted at 29k miles. One of the rear dampers is now leaking (I now have 112k on the clock) & although the car still feels decent, I'm sure the car would benefit from new shocks & dampers. I have enjoyed the ACS sports suspension on the car & would like to keep the comfort level that I have at the moment.
I cannot refurb the existing dampers to use on the car as that would take too long & ACS are not available anymore.
I am seriously considering the Birds kit, but would like to know that the comfort level is similar to the ACS setup. If it was ever so slightly firmer, that would be alright.
Anyone else using the Birds kit? especially up in Scotland

cheers, Mark

I've just had 1 front and 2 rear ACS dampers refurbed for 330 including postage by Bilstein, took a while but much more cost effective. I damaged a front shock 2 years back and was able to buy a new replacement, a rear was leaking in July. I replaced the two rears with Bilstein B4 from Autodoc with new covers and bump stops, they are fine and not so bad that I'll rush to fit the refurb ACS ones.
Mine had adaptive and i thought about temporarily putting that back in.

You could do similar?

And I'd ordered a new M340d that was cancelled by BMW in May, and prices have only gone one way since.

[McBeemer]

Originally Posted by V330d

I've just had 1 front and 2 rear ACS dampers refurbed for 330 including postage by Bilstein, took a while but much more cost effective. I damaged a front shock 2 years back and was able to buy a new replacement, a rear was leaking in July. I replaced the two rears with Bilstein B4 from Autodoc with new covers and bump stops, they are fine and not so bad that I'll rush to fit the refurb ACS ones.
Mine had adaptive and i thought about temporarily putting that back in.

You could do similar?

And I'd ordered a new M340d that was cancelled by BMW in May, and prices have only gone one way since.

Yeah, I had read your post earlier with interest.
I will have a think about doing similar, but I would need to get a garage to fit shocks. I had adaptive also, but coded it out after the adaptors from ACS were troublesome. My head says it is the right route, but my heart tells me just go for birds!
Due to my mileage both shocks & springs would benefit from updating.

Those rear B4 shocks on your post are cheap as temp replacements as well.

[Alscoob]

Some comments here.... https://f30.bimmerpost.com/forums/sh...rds+suspension

[danb1979]

Just to add my tuppenceworth to this

I considered the Birds kit for my F31 but when I looked into it; the price, IMO, for what they are, is steep, mored so for a static, non adjustable set up

The B4S shocks with Eibach pro kit springs (albeit as part of a FULL suspension overhaul) was the best thing I've done to the F31.

It drives and handles superbly; takes the rough country roads with ease (I run 18s all year round with non RFTs - Goodyear summers & all-seasons) and I've pressed on hard it it at times and not once have I felt the suspension needed to be bettered

For c£400 shocks / £200 for springs and another £200 for top mounts and OEM BMW rubber bits (perches/bump stops/dust boots etc) its a decent upgrade over OEM M Sport suspension

You just need to ensure you get the right shocks for your cars weight (on the tyre pressure sticker inside the door jam)

[TurboWeasel]

Common sense would steer towards the Birds kit if ACS can't be arsed to keep a stock of spares. Then again, you could just get the Bilstein number off the shock body and call up Bilstein UK and see if they're available?

There are a number of tuners who use Bilstein UK to retune off the shelf dampers, which have unique part numbers, but you might have some politics to deal with as they probably won't deal with the public directly.

As above, Eibach Pro springs with B4 is a very good value kit and probably 90% of what the Birds/ACS is in terms of day-to-day trundling about.

Evolve are working on their 4WD version of their B4 dampers, which could be another option when available. I've put over 1500 miles on their 2WD ones and with the Eibachs, they are superb.

[McBeemer]

Originally Posted by danb1979

Just to add my tuppenceworth to this

I considered the Birds kit for my F31 but when I looked into it; the price, IMO, for what they are, is steep, mored so for a static, non adjustable set up

The B4S shocks with Eibach pro kit springs (albeit as part of a FULL suspension overhaul) was the best thing I've done to the F31.

It drives and handles superbly; takes the rough country roads with ease (I run 18s all year round with non RFTs - Goodyear summers & all-seasons) and I've pressed on hard it it at times and not once have I felt the suspension needed to be bettered

For c£400 shocks / £200 for springs and another £200 for top mounts and OEM BMW rubber bits (perches/bump stops/dust boots etc) its a decent upgrade over OEM M Sport suspension

You just need to ensure you get the right shocks for your cars weight (on the tyre pressure sticker inside the door jam)

Thanks for your input Dan
Where did you manage to get your shocks & springs?
I take it all your OEM rubber bits just came from the dealers?

[danb1979]

Originally Posted by McBeemer

Thanks for your input Dan
Where did you manage to get your shocks & springs?
I take it all your OEM rubber bits just came from the dealers?

Shocks, springs and Sachs top mounts from Autodoc (via the app as it offers the best discount)

OEM rubber bits all from Cotswolds BMW with their forum discount

Part numbers on RealOEM etc

The project pages for the rebuild are here pal: https://f30.bimmerpost.com/forums/sh...1982298&page=7

Show's you what I bought etc

[Jon TDI]

The Birds kit is superb. Firm but not overly firm, just enough to make you confident that you’ll come out the other of a corner when pressing on.
My F31 is a daily driver so I didn’t want anything too crashy or stiff that would make it uncomfortable.

It’s just right for the UK roads.

[SEF]

Originally Posted by TurboWeasel

Common sense would steer towards the Birds kit if ACS can't be arsed to keep a stock of spares. Then again, you could just get the Bilstein number off the shock body and call up Bilstein UK and see if they're available?

There are a number of tuners who use Bilstein UK to retune off the shelf dampers, which have unique part numbers, but you might have some politics to deal with as they probably won't deal with the public directly.

As above, Eibach Pro springs with B4 is a very good value kit and probably 90% of what the Birds/ACS is in terms of day-to-day trundling about.

Evolve are working on their 4WD version of their B4 dampers, which could be another option when available. I've put over 1500 miles on their 2WD ones and with the Eibachs, they are superb.

I enquired with Evolve, and had a reply yesterday, they will be looking at doing xdrive dampers but have no current eta for when they may be available.

[martin10chk]

Suspension 'upgrades' are so subjective. What one person loves another hates. If you have been happy with the ACS setup then I would stick with it. There have been suggestions on here as to how to get a replacement part of a refurb.

[TurboWeasel]

Originally Posted by SEF

I enquired with Evolve, and had a reply yesterday, they will be looking at doing xdrive dampers but have no current eta for when they may be available.

That's a shame. I would go with the Birds kit if I were in your shoes, or see if they will sell you just the dampers?

I can't see the ACS and Birds being radically different tbh. They both use Eibach Pro springs and they both use Bilstein dampers, and both are tuned for improved ride and handling.

[McBeemer]

Unlike Dan, I'm not confident with fitting components & sourcing the correct items. I think I'm going to go with the Birds setup & get them fitted by my local indie garage. This guy is superb, as honest as they come & has a wealth of knowledge from years of experience. Shame that he is not too far away from retirement.
I might send the ACS dampers away to Bilstein & get them refurbed once they have been removed as well.
I really appreciate all the input & posting effort from everyone.

[TurboWeasel]

Yeah it might be worth getting the ACS ones refreshed to have on standby. Although if they sit around for years, there's no guarantee there'll be much gas pressure left when you come to use them

[MY340i]

Originally Posted by danb1979

Just to add my tuppenceworth to this

I considered the Birds kit for my F31 but when I looked into it; the price, IMO, for what they are, is steep, mored so for a static, non adjustable set up

The B4S shocks with Eibach pro kit springs (albeit as part of a FULL suspension overhaul) was the best thing I've done to the F31.

It drives and handles superbly; takes the rough country roads with ease (I run 18s all year round with non RFTs - Goodyear summers & all-seasons) and I've pressed on hard it it at times and not once have I felt the suspension needed to be bettered

For c£400 shocks / £200 for springs and another £200 for top mounts and OEM BMW rubber bits (perches/bump stops/dust boots etc) its a decent upgrade over OEM M Sport suspension

You just need to ensure you get the right shocks for your cars weight (on the tyre pressure sticker inside the door jam)

I’ve had the full birds setup on my 335d back in 2019, given they were the most local specialist I had at the time. Great bit of kit. I’m now running the same setup as you are: eibach pro kit and new oem shockers on my 340i, with a fast road geo. I’d say it’s approx 85% the feel of the birds kit. It’s that extra 15% sthat birds kit gives.

Money no object, birds any day of the week, but bang for buck, Eibach springs + oem replacement shocks from Autodoc is great too.

[danb1979]

Originally Posted by MY340i

I’ve had the full birds setup on my 335d back in 2019, given they were the most local specialist I had at the time. Great bit of kit. I’m now running the same setup as you are: eibach pro kit and new oem shockers on my 340i, with a fast road geo. I’d say it’s approx 85% the feel of the birds kit. It’s that extra 15% sthat birds kit gives.

Money no object, birds any day of the week, but bang for buck, Eibach springs + oem replacement shocks from Autodoc is great too.

That's it; if the F31 was more of an every day fast road driver (ie if it were a 340i or a 328i etc) then I may have spent the Birds amount and gone the whole hog

But it's a daily for the wife to commute to work and back and the car we use for the road trips to the Highlands / down to Anglesey and beyond etc

The Bilstein B4S/Eibach pro kit springs are perfect for all of that & more; more so as they were part of a full suspension overhaul; I'd say that's what made the biggest difference all in (at some expense as well)!

If I were doing just shocks & springs; I'd probably have gone Birds...

[mapyn]

are the b4s shorter for lowering? I'm keen to retain std ride height

[danb1979]

Originally Posted by mapyn

are the b4s shorter for lowering? I'm keen to retain std ride height

No; the B6s and B8s are

B4s and B4S's will retain standard height if you use the OEM springs

They'll allow the Eibach pro kit springs to lower about 10-15mm MAX over M-Sport

My F31 only lowered around 10mm

[TurboWeasel]

Just to be nerdy, everything in Bilstein's catalogue for an M sport car has shorter shocks compared to the base suspension (335d, 320i etc).

So for an M sport, B8 & B4 "for M technology suspension" are the 2 choices.

B6 is for the base spec if keeping the stock ride height.

If lowering an M sport on Eibach springs, I recommend genuine F80 bump stops. Although the rear only drops 5mm, the shorter bump stops improves the ride quality. The standard M sport rear bump stops are ridden on permanently.