Z4M ride quality on KW V3/other coilovers?

[ss1977]

Hello all,

I'm after some advice and owner experiences re the ride quality of a Z4M on KW V3 or other coilovers, having previously owned a Ruby Black Z4M Coupe running standard suspension and OEM CSLs, which I found rather harsh riding.

I currently have a very nice 2003 Z4 3.0 riding on upgraded Eibach springs and Bilstein dampers, which I bought off a forum member, but have been looking at getting back into a Z4M next year (I'm missing the firecracker top end of that S54 engine!). Probably going for a roadster this time round.

I would be really grateful if any forum members with experience of running coilovers are able to offer some opinions regarding the ride quality when compared to something such as a BMW 5-series, which I also own. If, for example, I were to score the ride quality of my M5 as 10/10, where would the Z4M on coilovers sit on softer settings? 5/10?

Any views and opinions would be very much appreciated!

Simon

 

[MrPT]

No idea about the M5 comparison. Forum member monaco_blue had that exact combination of cars so might be your man!

I found the M ride with V3s and stock 18s to be an improvement over an si on sport springs with 18s. Stiffer but much better with small bumps at all speeds. Some of the difference would have been down to the lower profile tyres on the si, but the si also got unsettled more easily on undulating country roads and would “thud” into small potholes in a way that upset the whole car, whereas the M on V3s punches in and out again without much fuss (ish!). Beyond that basic behaviour, they need properly setting up to get the most out of them. The rear is particularly tricky as they bottom out quite easily with softer compression settings, but you need to keep the softness as the rear of the car is light.

But I’d say the ride is mainly a bonus, given the handling improvements. You’ll notice more of an improvement in ride quality (overall) by dropping back to 18s or going up a profile size on 19s.

 

[Argenta]

Interested in views too, as I’m thinking of using KWV3. I now have just Eibach Pro springs, a very cheap way of getting loads better comfort over std.

 

[Fishy Dave]

Interested in views too, as I’m thinking of using KWV3. I now have just Eibach Pro springs, a very cheap way of getting loads better comfort over std.

I have the same set up as you, Eibachs on standard 55k mile dampers. I can live with them but they still crash on harsh roads and struggle to control the car on track at places like Castle Combe or Anglesey with high speed undulations.
I came very close to buying the V3 last week, but two things stopped me, having read loads of views on here and chatting with Tom. The first was the need to run spacers if using 224s, the second was having separate adjustment of bump and rebound. I'm not lazy and do enjoy tinkering, BUT, I'd also like to make life easy when swapping from road to track.
The Bilstein PSS10 kit has just one large knob on the bottom of each damper, with ten clicks. Users on here report it's so easy to crouch down and make the adjustment, that sounds good to me.
I'm not knocking the KWV3 which sound superbly built units and if you can perfect both damping adjustments are possibly better than the Billies, but ease of use of the PSS10 sounds good to me and saves the small extra expense of the spacers and nuts.
I will be fishing around for the right deal shortly..... 8)

 

[Beedub]

yeah the adjustment on the KW is a PITA.

However they have updated the design with an under arch adjustment reciprocal .

 

[MrPT]

I don't find it too bad (although I have the under-arch rear adjustment Beedub is talking about). You can do it pretty anywhere with level ground and the help of a plank/kerb, e.g. a random hotel near Carlisle where the kitchen staff watch on, bemused, as you slackened things up for the long cruise home... :roll:

Those Bilsteins look great, Dave. Never seems to work well when rebound and compression damping go in opposite directions anyway. Remember to tape up exposed threads to keep them clean! Especially if you are going to go to that crazy airfield/quarry again...

 

[Fishy Dave]

Never seems to work well when rebound and compression damping go in opposite directions anyway.

Do you mean on the KW?

That's a good tip on the threads, never thought of using tape. This was a problem on the Caterham with grit getting in the alloy collars.

Especially if you are going to go to that crazy airfield/quarry again...

Never again, my bumper still has the chips to prove it, a front end respray may be on the cards next year. :thumbsdown:

 

[Fishy Dave]

Repeating what the OP asked, any other views on how the ride has changed since fitting coilovers to your M?

 

[Beedub]

Repeating what the OP asked, any other views on how the ride has changed since fitting coilovers to your M?

KW CLUBPOSRT.

a track biased damper, Stainless steel bodies, lots of other nice bits in the construction of these units, they also cope with the UK winter really well ( i have used them on a previous DD in V3 form) , adjustment is kinda painful on the roadster, which means actually removing the damper to get to the top adjustment, the bottom OLDER style adjustment is imo better, its covered but alittle plastic unit and you use a pin to move through the adjustment window.

The club sports come with linear springs up front and helper springs with solid uniball outing system, a big chunk of rubber is removed from the stock setup.

Feel and control is up by a massive amount, ride comfort i think has decreased by some way, this can be addressed somewhat by changing the settings but its such a ball ache at the rear that i leave it in an ALL round setting which KW recommended for a nurburgring track session which seemed ok to me due to that places crazy bumps etc.

the fire wall braces appear to transmit alot more feedback into the cabin and reinforcement is recommended imo, whats crazy is , on the road the way the car deals with the bumps is definitely more controlled and does thud through the cabin as you'd expect, its a firm feeling but the dampers are really doing their bit, the gt4 i recently tried felt very similar in the way it rode and dealt with general road conditions.

In track conditions its nothing short of amazing, braking is improved, pitch and squat is gone, all 4 wheels are working much better underbraking without the car unloading one end. Combine some proper tyres and the cars handling teamed with the already awesome steering it feels amazing, id guess the v3 offers most of the above with much more comfort but still very trackable with the dampers dialled up. Needing spacers up front would not put me off as the additional track has benefits.

Sorry for typos, on mobile phone.

 

[MrPT]

Never seems to work well when rebound and compression damping go in opposite directions anyway.

Do you mean on the KW?

Hah, no I didn't mean that. Although that does do your head in too sometimes - lots of "lefty loosey, righty tighty" required.

I mean you rarely need loads more rebound damping than bump (and vice versa) so 2-way are only helpful for fine tuning. Having said that, I think the Z4M might benefit more from 2-way adjustment than most, because you sit very close to rear axle and the rear springs are short, so small changes are very noticeable.

I don't actually think that a good compromise between not bottoming out, ride quality and rear grip is actually achievable - maybe others have had better luck? This might be part of the reason the OEM suspension ended up with such weird tuning.

 

[Beedub]

Never seems to work well when rebound and compression damping go in opposite directions anyway.

Do you mean on the KW?

Hah, no I didn't mean that. Although that does do your head in too sometimes - lots of "lefty loosey, righty tighty" required.

I mean you rarely need loads more rebound damping than bump (and vice versa) so 2-way are only helpful for fine tuning. Having said that, I think the Z4M might benefit more from 2-way adjustment than most, because you sit very close to rear axle and the rear springs are short, so small changes are very noticeable.

I don't actually think that a good compromise between not bottoming out, ride quality and rear grip is actually achievable - maybe others have had better luck? This might be part of the reason the OEM suspension ended up with such weird tuning.

as far as im aware the damping is the same on both sides of the car, start from hard or off ( think of your taps in the house) clockwise to the end of adjustment then turn anti clockwise in each increment, if you swapping this around for the other side your dampers aren't set correctly. if you work on the clockwise / anti clockwise way of thinking you will always get it right

 

[ss1977]

Thanks for the replies everyone (and thanks for the info on monaco_blue MrPT!) . Think I'll stick with the standard 224s this time round, rather than going for the CSLs and then possibly the KW V3 coilovers. I've read that the suspension is softer on the roadster anyhow, when compared to the coupe; has anyone had both and able to provide any feedback on this?

As an aside, I was in my current 3.0 Z4 on Friday afternoon driving down an undulating (although not potholed or particularly badly surfaced) country B-road which I know pretty well and I really struggled to stay with a 2006 A4 3.0 TDI cab because the Z4 was bucking around so much. It was wet and cold and I know the A4 has Quattro 4WD, but the M5 would of had no problem IMO. If the KW V3s are able to offer even some of ride compliance that the M5 has, then I'm in

 

[BMWZ4MC]

Thanks for the replies everyone (and thanks for the info on monaco_blue MrPT!) . Think I'll stick with the standard 224s this time round, rather than going for the CSLs and then possibly the KW V3 coilovers. I've read that the suspension is softer on the roadster anyhow, when compared to the coupe; has anyone had both and able to provide any feedback on this?

As an aside, I was in my current 3.0 Z4 on Friday afternoon driving down an undulating (although not potholed or particularly badly surfaced) country B-road which I know pretty well and I really struggled to stay with a 2006 A4 3.0 TDI cab because the Z4 was bucking around so much. It was wet and cold and I know the A4 has Quattro 4WD, but the M5 would of had no problem IMO. If the KW V3s are able to offer even some of ride compliance that the M5 has, then I'm in

My RS4 has dynamic suspension and handles poorly maintained country roads at far greater speeds and inspires much more confidence than my Z4MC on KW Clubsports. However take it to a tight, smooth bend and the Zed just sticks with increasing speed where the Audi would wash out into understeer.
The Clubsports break my teeth when I run over cats eyes, but as Beedub’s has already described, with sticky tyres it accelerates, brakes and corners like a 100k Porsche. In direct comparison on a track, a 996 GT3 couldn’t keep up and a 997 GT3 was only quicker in a straight line.