Suspension Upgrade Advice
- Thread starter MichaelPorter80
- Start date
Probably also worth mentioning that you’ll need a 5-10mm spacer on the front axle with the V3s, due to the conical shape of the progressive front spring.
The above doesn’t bother me (it looks better and also clears my brakes!). The only real issues I’ve had with them are:
i) they have a metal spring perch with a composite adjustment wheel that you can damage if you don’t keep your threads clean (easy once you know how); and
ii) the rear spring travel is less than stock and ”bottoming out” can be a problem with soft bump settings. People who have tested the spring rates on a jig have found that you don’t get the full ~4” of travel you get with stock, so coil binding is the likely culprit. Sounds horrendous, given how stiff the rear is anyway, but it’s actually the rear rebound which causes a lot of discomfort, so you can run (for example) 50% open bump damping and 90% open rebound damping and it works well.
Still the odd, terrifying thunk, mind! But with no visible wear of the bump stops or top mounts in 25k miles, it’s hard to draw definitive conclusions about damage.
The above doesn’t bother me (it looks better and also clears my brakes!). The only real issues I’ve had with them are:
i) they have a metal spring perch with a composite adjustment wheel that you can damage if you don’t keep your threads clean (easy once you know how); and
ii) the rear spring travel is less than stock and ”bottoming out” can be a problem with soft bump settings. People who have tested the spring rates on a jig have found that you don’t get the full ~4” of travel you get with stock, so coil binding is the likely culprit. Sounds horrendous, given how stiff the rear is anyway, but it’s actually the rear rebound which causes a lot of discomfort, so you can run (for example) 50% open bump damping and 90% open rebound damping and it works well.
Still the odd, terrifying thunk, mind! But with no visible wear of the bump stops or top mounts in 25k miles, it’s hard to draw definitive conclusions about damage.
AndyBeech said:
You don’t need to do that. The top adjusts via a dial inside the wheel arch and the bottom via a hole in the bottom of the shock.
I’ve changed mine in pub/hotel car parks. Get some looks, mind...
I should caveat the note re the rear springs - I don’t actually know whether the “thunk” is a genuine hard stop in the suspension or whether it’s just the coils becoming unbound on extension (and hammering the chassis). I suspect it’s the latter but need to do some experiments to find out.
MrPT said:AndyBeech said:
You don’t need to do that. The top adjusts via a dial inside the wheel arch and the bottom via a hole in the bottom of the shock.
I’ve changed mine in pub/hotel car parks. Get some looks, mind...
I should caveat the note re the rear springs - I don’t actually know whether the “thunk” is a genuine hard stop in the suspension or whether it’s just the coils becoming unbound on extension (and hammering the chassis). I suspect it’s the latter but need to do some experiments to find out.
Ah ok thanks, yes the revised design, forgot about that!
Argh, can get the PSS10's for £1580, V3's cheapest seems around £1850-1900. Gravitating towards the Bilstein's but don't really know why! Not just the small price difference TBH but they just sound a bit easier to set up even if not as adjustable as the V3's or quite as well built potentially...decisions decisions. (Sorry for thread hijack OP, was gonna ask a similar question so saves 2 separate topics!)
I'd go KW every time for a couple of reasons...
1. Adjustability, they are more adjustable and it will allow you in time to get them how you want
2. They are a twin tube damper not a monotube like the bilstein, hence they ride much nicer
3. The coating is excellent on them, they look like new after several winters when you give them a wipe down
4. People tend to have problems with Bilsteins, I know that's a bit generic but just over the years you pick up comments etc.
5. You can upgrade them to clubsports if you want at a later date
All in my opinion obviously, I've been running continuously on cars KWs since 2005, I've never had one issue
1. Adjustability, they are more adjustable and it will allow you in time to get them how you want
2. They are a twin tube damper not a monotube like the bilstein, hence they ride much nicer
3. The coating is excellent on them, they look like new after several winters when you give them a wipe down
4. People tend to have problems with Bilsteins, I know that's a bit generic but just over the years you pick up comments etc.
5. You can upgrade them to clubsports if you want at a later date
All in my opinion obviously, I've been running continuously on cars KWs since 2005, I've never had one issue
MrPT said:
Thanks again. I’d forgotten about the need for spacers with the KWs.
As for reliability, I too have read of a couple of issues with the Bilsteins on the Z4M but I have also been warned off KW for similar reasons!
I’d look elsewhere but most other suspension brands are more focused on track performance and I’d worry about ruining the road manners (what there is of them anyway!)
I did read on another forum of someone getting some revalved Bilsteins for the Z4M, I’ll try and find it again and see where he got to.
For what it’s worth, my impression and personal experience is that reliability is a KW strongpoint. Their support - again, in my experience only - has been excellent. They are still the kind of company you can have a long, nerdy email conversation with someone technical who will go out of their way to help. I don’t even have a valid warranty with them.
If you look more generally for the Bilstein's on other similar cars there's plenty of people running them with no issues, same with KW's. The usual 'you only hear when people have problems' applies so you have to weigh up stuff you hear on the internet. On the basis of that can't see a lot to choose between the Bilstein and KW offerings. Apart from a small(ish) difference in cost (£300-400) and KW have better adjustability if you want that.
Anyway, I've pulled the trigger on the Bilstein's, I'll post up with thoughts when I get them fitted next year. I'm getting a total undercarriage refresh after 95k miles on standard stuff so probably not a fair comparison though!
Anyway, I've pulled the trigger on the Bilstein's, I'll post up with thoughts when I get them fitted next year. I'm getting a total undercarriage refresh after 95k miles on standard stuff so probably not a fair comparison though!
MrPT said:
Yeah got quite a good deal on the Bilstein's so we'll see how they go! They've got a lifetime warranty so apart from the faff of getting them off the car *if* something goes wrong, they are fairly well covered in that respect.
Beanie - I'll certainly do a thread once it goes in for the work. Making my eyes water a bit thinking how much I've spent on parts over the last few months for the refresh...deffo into a good thousand or so and that's without the suspension included but it's time to bite the bullet and give it some pampering. Pretty much gathered all the parts myself for an Insp 2 plus general refresh, hopefully will save a bit on labour as a lot of stuff checked on the Insp 2 is getting replaced but in no illusions that it's probably going to be a good few thousand again in labour...and then some potentially (still considering doing the head gasket as preventative...).
Likely getting Darragh at Everything M3 to do the work. Although we've not talked costs yet I can imagine he'll offer as good value as anywhere else plus you have more of a personal touch with the work that don't get with some other bigger garages (hopefully he'll let me hang around a bit and get involved with some of the work!).
It will all be worth it in the end and it’s bound to feel great when it’s done.
I always look at these costs compared to the depreciation on something newer. One way or another you’ve got to spend, but it’s far nicer buying parts than seeing the money evaporate!
I’ve only heard good things about Everything M3 so you should be in good hands
I always look at these costs compared to the depreciation on something newer. One way or another you’ve got to spend, but it’s far nicer buying parts than seeing the money evaporate!
I’ve only heard good things about Everything M3 so you should be in good hands
beanie said:It will all be worth it in the end and it’s bound to feel great when it’s done.
I always look at these costs compared to the depreciation on something newer. One way or another you’ve got to spend, but it’s far nicer buying parts than seeing the money evaporate!
I’ve only heard good things about Everything M3 so you should be in good hands
Cheers, I hope so!
You are right of course, should be better than new at least undercarriage wise when it's done. Still have nightmares paying £16 for one diff bolt though, honestly never knew a few bolts and fixings could cost so much, cheers BMW :lol: Darragh's a good guy, did my rod bearings, knows his stuff for sure!
RedUn said:Look forward to the review, make sure to get the geo done properly to make the most of them
Certainly will, when I can find someone decent in the South to do it! Not had the best experience with some of the hunter alignment guys down this way so far....
I know an excellent place, bit of a drive mind just outside Birmingham...AndyBeech said:RedUn said:Look forward to the review, make sure to get the geo done properly to make the most of them
Certainly will, when I can find someone decent in the South to do it! Not had the best experience with some of the hunter alignment guys down this way so far....
they use Beissbarth too 8)Let me know if your interested and I'll PM details
