Handling/Coilover Opinions Please
- Thread starter RedUn
- Start date
What about considering the Bilstein B16 PSS-10? The downside for some, but the upside for others is that the PSS-10 has less settings to fine tune the damper setting. You only have 10 settings between soft and hard. On a V3 and Clubsport you can fine tune your suspension in a more detailed way (if you are a specialist and know what you are doing). The PSS-10 way easier to set up and to experimented with the settings.RedUn said:BMWZ4MC, what settings are you running your clubsports on? Do you leave them on your track settings on the road?
I don't actually mind a firm ride as long as it's well damped and controlled but I know what you are saying, i'll no doubt run with the thicker ARB's and soften the dampers up on the road and then adjust for track/ring use. I'll be going for V3's at a minimum
Good luck on the weight reduction front, it's not a cheap game, I knocked a 100kg out of my S2000 and it cost me a fortune as I wanted to keep the car fully roadworthy inside and not strip it out etc.
Tertius, did you have to pay for the changes to your Intrax or did they do it free of charge?
I have them fitted on my roadster a couple of months a go: http://www.z4-forum.com/forum/viewtopic.php?f=9&t=66229&p=978483&hilit=Franzino#p978483
Exdos have them fitted on his Z4M coupe for a longer time and really likes them…
For me it was a big upside that the Bilstein PSS-10 can be set-up a little higher. My Z4M is now at exactly the same ride height as with my OEM dampers and Eibach springs. I would not want it any lower. Is a Clubsport a suspension that is less versatile considering ride height and always a lot lower then stock (even on highest setting)?Beedub said:
exdos said:I think I can sum up here: ANY of the known brands of adjustable suspensions for the Z4M will considerably improve the handling and ride (if set up soft enough for road settings) of the Z4M. All the brands correct the gross imbalance of spring/damper rates of the OEM suspension. It would appear that all of us who have fitted aftermarket suspension are satisfied customers of the respective brands we've fitted and I'm sure that we would also have been satisfied if we'd fitted any of the other brands mentioned in this thread. If you really want to enjoy a considerably improved Z4M then you simply MUST upgrade the suspension. FACT
Good reading this thread. Guys if my aim was to make the car a road only weapon what would you do to improve the ride quality and handling? My aim is to get a more sure planted feel at speed, and more confidence in corners whilst still maintaining a little bit of suppleness to soak up our bad road surfaces!
Guys thanks for all your inputs and comments - I've made a decision that i'll be going with KW and some H&R ARB's, I've just not decided on V3's or Clubsports yet, more reading, thinking and talking required...
Franzino, I have thought about Bilstein but being a bit boring like I am, i'll happily spend hours playing with all the different settings on the KW's
For information, the minimum drop on clubsports is 25mm front and 0mm rear.
Fast3000 - I think the Eibach springs and OEM dampers would be ideal, if you wanted a bit "more" then maybe look at the Bilsteins or KW V3's - speaking from lots of reading and no experience (on this car!)
Franzino, I have thought about Bilstein but being a bit boring like I am, i'll happily spend hours playing with all the different settings on the KW's
For information, the minimum drop on clubsports is 25mm front and 0mm rear.
Fast3000 - I think the Eibach springs and OEM dampers would be ideal, if you wanted a bit "more" then maybe look at the Bilsteins or KW V3's - speaking from lots of reading and no experience (on this car!)
Does anyone run KW V3 in a city? or specifically near speed bumps? 
There's some pretty aggressive traffic calming measures in SW London... i think the worst speedbumps near me i'd be fine with a 1" lower frontend, but no more. One thing about the Z4MC i really love is how stiff and rigid it is, i want more stiff-and-rigid'ness :evil:
Not fussed about London potholes, i avoid them anyway, but i'd be keen to make sure it handles for B-roads, rather than track tarmac (hence kwv3 may be overkill... maybe just uprating other suspension elements alongside eibachs/H&R's?)
There's some pretty aggressive traffic calming measures in SW London... i think the worst speedbumps near me i'd be fine with a 1" lower frontend, but no more. One thing about the Z4MC i really love is how stiff and rigid it is, i want more stiff-and-rigid'ness :evil:
Not fussed about London potholes, i avoid them anyway, but i'd be keen to make sure it handles for B-roads, rather than track tarmac (hence kwv3 may be overkill... maybe just uprating other suspension elements alongside eibachs/H&R's?)
jimmybell said:Does anyone run KW V3 in a city? or specifically near speed bumps?
There's some pretty aggressive traffic calming measures in SW London... i think the worst speedbumps near me i'd be fine with a 1" lower frontend, but no more. One thing about the Z4MC i really love is how stiff and rigid it is, i want more stiff-and-rigid'ness :evil:
Not fussed about London potholes, i avoid them anyway, but i'd be keen to make sure it handles for B-roads, rather than track tarmac (hence kwv3 may be overkill... maybe just uprating other suspension elements alongside eibachs/H&R's?)
KW V3 is great anywhere if you've got it set up properly. Lowering a car so that it becomes undrivable in the urban environment is pointless.
Your desire for more stiffness is at odds with optimum handling on B-roads: adjustable suspension is best set-up at the softer end of the scale for this environment.
After a drive of a 997.2 GT3 last night, I can now really appreciate what a quality suspension feels like on roads I use myself for quick blasts. Night and day.....
So with that in mind, can I ask a quick question whilst on the topic of KW V3's. Are adjustable top mounts essential to allow you to dial in a fast road alighnment, or will the OEM top mounts do?
G
So with that in mind, can I ask a quick question whilst on the topic of KW V3's. Are adjustable top mounts essential to allow you to dial in a fast road alighnment, or will the OEM top mounts do?
G
gwatson said:
Camber/caster plates are not essential. I have them on my Z3MC but have OEM top mounts on my Z4MC. I keep banging the drum that it's toe which makes the most difference to handling, and that's adjusted on the tie rods. Likewise, if you want to fit caster/camber plates, adjust caster to get more dynamic camber, rather than adjusting camber, itself.
exdos said:gwatson said:
Camber/caster plates are not essential. I have them on my Z3MC but have OEM top mounts on my Z4MC. I keep banging the drum that it's toe which makes the most difference to handling, and that's adjusted on the tie rods. Likewise, if you want to fit caster/camber plates, adjust caster to get more dynamic camber, rather than adjusting camber, itself.
Thanks John, that's what I thought\hoped. Although you obviously have the ACS kit. Anyone care to comment specifically on KW's? I know some other suspension kits you need to use aftermarket top mounts.
Car is just about to turn 60k miles, so thinking of replacing the top mounts with news one. Would you recommend that?
I remember on my E36 M3 Evo track car you would fit the left hand top mount to the right hand side and vice a versa, gave a lot more negative camber (and castor I think), was a great tip. Don't think it'll work on the Z4M setup though
Your Z3M coupe could of be the same! I don't know what it will be on a Z4M because I still have OEM top mounts. I experimented with the caster/camber plates on my Z3MC, where I adjusted caster/camber on one side only and took measurements of the dynamic camber angle with a quarter turn on the steering wheel, which I could compare against the other front wheel acting as control. Increasing caster certainly increased dynamic camber much more than increasing static camber, as is stated in many texts on this subject. However, for me though, the big difference is in the handling: I find increasing negative camber at the front makes the car twitchy, bump-steer and "squirrel" on braking, whereas increasing caster to increase the dynamic camber improves the handling (provided there's no toe-out) because the car then has a tendency to naturally steer straight ahead, which overcomes the twitchiness, bump-steering and squirrelling on braking.
Here's an extract from the Whiteline website (in 2007) on caster:
Caster – What is it and why is it important?
Caster is the backward or forward tilt of the steering axis. Vehicle manufacturers are aware of the advantages of caster and as each new model is released the amount of caster specified increases. For example, the VB Commodore was released with around ½ degrees positive castor; the VT now comes standard with around 9 degrees!
Why, because the disadvantages of high levels of castor are being overcome. Rack and pinion steering means less play, lower Ackerman levels, smaller scrub radius (zero is now very common), better and lower profile radial tyres means less sidewall deflection and higher tolerance to greater slip angles. But the greatest obstacle, that of heavy steering effort, has all but disappeared with the universal acceptance of power steering. That’s why Whiteline developed a range of adjustable radius rods for Commodore, which allow an additional 2.5deg positive caster on VB to VS.
High levels of positive caster equate to dynamic negative camber on turn when you need it most. (Have a look at the front wheels of a Mercedes or Audi when parking.) Whiteline continues to put heavy emphasis on additional positive caster when designing new suspension packages.
Caster - "When too much caster is never enough"? – 5 reasons why.
Maximise tyre contact patch during roll
Improve turn-in response
Increase directional stability
Maximise tyre contact patch during braking and acceleration
Improved steering feel and self-centre
Increases dynamic negative camber (on turn)
Castor Vs camber, try castor first. Why?
Camber doesn’t improve turn-in, positive caster does.
Camber is not good for tyre wear.
Camber doesn’t improve directional stability.
Camber adversely effects braking and acceleration.
Here's an extract from the Whiteline website (in 2007) on caster:
Caster – What is it and why is it important?
Caster is the backward or forward tilt of the steering axis. Vehicle manufacturers are aware of the advantages of caster and as each new model is released the amount of caster specified increases. For example, the VB Commodore was released with around ½ degrees positive castor; the VT now comes standard with around 9 degrees!
Why, because the disadvantages of high levels of castor are being overcome. Rack and pinion steering means less play, lower Ackerman levels, smaller scrub radius (zero is now very common), better and lower profile radial tyres means less sidewall deflection and higher tolerance to greater slip angles. But the greatest obstacle, that of heavy steering effort, has all but disappeared with the universal acceptance of power steering. That’s why Whiteline developed a range of adjustable radius rods for Commodore, which allow an additional 2.5deg positive caster on VB to VS.
High levels of positive caster equate to dynamic negative camber on turn when you need it most. (Have a look at the front wheels of a Mercedes or Audi when parking.) Whiteline continues to put heavy emphasis on additional positive caster when designing new suspension packages.
Caster - "When too much caster is never enough"? – 5 reasons why.
Maximise tyre contact patch during roll
Improve turn-in response
Increase directional stability
Maximise tyre contact patch during braking and acceleration
Improved steering feel and self-centre
Increases dynamic negative camber (on turn)
Castor Vs camber, try castor first. Why?
Camber doesn’t improve turn-in, positive caster does.
Camber is not good for tyre wear.
Camber doesn’t improve directional stability.
Camber adversely effects braking and acceleration.
gwatson said:Thanks John, that's what I thought\hoped. Although you obviously have the ACS kit. Anyone care to comment specifically on KW's? I know some other suspension kits you need to use aftermarket top mounts.
Car is just about to turn 60k miles, so thinking of replacing the top mounts with news one. Would you recommend that?
I remember on my E36 M3 Evo track car you would fit the left hand top mount to the right hand side and vice a versa, gave a lot more negative camber (and castor I think), was a great tip. Don't think it'll work on the Z4M setup though
The KW kits can be used with the OEM top mounts, and IIRC, the Clubsport kit is offered with caster/camber plates at a very good price. There would be no harm in fitting new top mounts, and if you do, can I have your old ones to experiment with making some fixed caster plates?
Yes, you can swap the front top mounts of the Z3MC to get over 3 degs of negative camber. I tried it for a while, but I found it far too twitchy for fast road use, so that's when I tried caster/camber plates and found that caster was actually the preferred adjustment. The driving experience is far more relaxed.
exdos said:The KW kits can be used with the OEM top mounts, and IIRC, the Clubsport kit is offered with caster/camber plates at a very good price. There would be no harm in fitting new top mounts, and if you do, can I have your old ones to experiment with making some fixed caster plates?
Yes, you can swap the front top mounts of the Z3MC to get over 3 degs of negative camber. I tried it for a while, but I found it far too twitchy for fast road use, so that's when I tried caster/camber plates and found that caster was actually the preferred adjustment. The driving experience is far more relaxed.
Yeah of course, however it probably won't be until May next year as I'm in the states on holiday and planning on picking up a load of parts from a local dealer to overhaul the car. Sick of paying £'s.... Also need to decide if I want to invest in the car, or move on :?
So what's a caster plate? Is it effectively an angled spacer?
tertius said:
What you need is a caster/camber chart/table, if there's a published one. As an indicator, I've just been out and measured the camber changes on my Z3MC which has approximately 9 degrees of caster:
Static camber = -1.7 degs,
90 degree turn on steering = -3.4degs
180 degree turn on steering = -5.5 degs
I measured the camber with a clinometer app on an Android tablet, so the figures are a reasonable approximation.
gwatson said:
It would be like these fixed camber plates http://www.turnermotorsport.com/p-2...e46-not-m3-turner-motorsport-streettrack.aspx except that instead of moving the tops of the dampers towards each other, which increases negative camber, they would be engineered to move the tops of the dampers rearwards, to increase caster. As far as I know, nobody makes them, but since caster increases dynamic negative camber, personally, I think that this would be a preferable way of doing things.
gwatson, I'm sure I've read you can swap the top mounts on the Z for more camber, may have just made that up though!
It also sounds like you are in a similar position to me with the car, if it's any help, I figured without spending upwards of 40k and more than likely 60k there's actually not much else with the same layout that would be much better, I personally wasn't convinced in any case.
I also got offered my money back after two years of ownership, which has never happened before I might add, so I figured, what's the harm in keeping it and sorting out the handling once and for all? That's my plan anyway once I make my mind up eventually on what suspension I actually want
Gents, another question, which top mounts are you using at the rear? OEM or uprated? Any one running adjustable rear arms as well?
It also sounds like you are in a similar position to me with the car, if it's any help, I figured without spending upwards of 40k and more than likely 60k there's actually not much else with the same layout that would be much better, I personally wasn't convinced in any case.
I also got offered my money back after two years of ownership, which has never happened before I might add, so I figured, what's the harm in keeping it and sorting out the handling once and for all? That's my plan anyway once I make my mind up eventually on what suspension I actually want
Gents, another question, which top mounts are you using at the rear? OEM or uprated? Any one running adjustable rear arms as well?