Ok, so last weekend I had a real eye-opener during a day out in the Ardennes in Luxembourg on the twisties...on smooth roads, the car behaves well, except that if you brake too hard, too late, the rear wants to pass the front....odd, as I never had it on any generation M3 I used to own, they were much more stable...but then, when the roads become crap, the handling is awfull...it seems like an impossible task to keep the car where you want it to be, as it dances and jumps all over the place...that is a big dent in your confidence...I had H&R springs, which are now replaced by Eibach pro and eventhough the ride seems a bit less jumpy I don't expect a complete transformation...what do you advise to get rid of both these annoying characteristics? As I spend 99% on roads like this and not on a smooth track, I would really want to sort it out...any input is welcome as I'm even thinking about swapping the car for an E92 M3, which should be much more balanced... but the thing is, that I really fell in love in about anything about the Z4M, except the handling on bad roads...
Crappy roads = crappy ride...
- Thread starter tomwac
- Start date
Sounds very odd, are you sure nothing is wrong? Are the springs properly matched to the dampers? Mine can be a little bumpy on rough roads as it's a relatively stiffly sprung car, but its certainly not uncomfortable. I've never had the rear end trying to overtake the front, that's for sure...
Well, I'm not sure what it is...I have new eibach springs on oem dampers...the car has about 27000miles so I would guess that the dampers are not shot yet...mikedav said:
The rear trying to overtake the front was scary and it happened a few times...you feel the rear coming and then the car just understeers in the direction of the trees...the bumpy/jumpy ride...that's scary...at one point, after a big bump, I suddenly found myself on the other lane, in a corner :? ...to clarufy, the pace we were driving was not to do some sightseeing, but like said, I never experienced something like this before ... except for the CSL's, eibachs, the car is bone stock...
I'd start with the geo too. Did you have the geo done when you had the springs replaced?
tomwac said:
There is a pin next to the top mounts, get your alignment guy to pull them out and then you can get a bit more camber on the front, i've got mine at -1.6 if i remember correctly. Doesnt make a world of a difference but it's still noticable.
Check this post out: http://www.zpost.com/forums/showpost.php?p=6920687&postcount=5
Doesn't a coilover stiffen up the suspension even more? And which are the 'proven' setups on a Z4M? KW, Bilstein, Intrax, Moton? Something which doen not need a spacer...ZM4000 said:It is time for a proper coilover set.
The z4m has a bad road habit nothing to do about ir unless a good coilovers set
wouln't 19 inch CSL's combined with stiff and lower spring scrap the car's priginal set up? Surely it would tramline like hell making it very jumpy and run out of suspension travel? :?
All you guys on pot holed UK B roads driving a similar set up - what's it like?
All you guys on pot holed UK B roads driving a similar set up - what's it like?
Hi tomwac, I had noticed my car could get unsettled when pushing on a bit on a 'schadden strasse' although mine is only a 3.0Si Coupe . I have changed to the Eibach pros, which you have and I have 19" wheels with non RFT tyres. The only other changes I have made are the fitting of powerflex poly bushes to the track control arms and CSL RTA bushes (Yours might be these already, someone on here will know) and a Turner Motorsport bush limiter kit which reduces the camber change on the rear wheels. These mods have IMHO improved the stability of the car without ruining the ride quality. The steering especially turn in is more positive and the rear does feel more planted.
If you are around this way you are more than wellcome to drop by and have a drive of mine to compare. I live between Offenburg and Frieburg less than 5 mins off the A5 Autobahn @ Ettenheim.
If you are around this way you are more than wellcome to drop by and have a drive of mine to compare. I live between Offenburg and Frieburg less than 5 mins off the A5 Autobahn @ Ettenheim.
On lumpy bumpy roads the car can be twitchy and jump about a bit but generally it's pretty surefooted except on the very worse roads. The 19's might not help much. I thought I'd a problem with mine a few weeks back, first drive of any distance/speed since winter and i was struggling to flow bend to bend on some Welsh 'B' roads. when I came to analyse it I realised that I was driving a lot quicker than perhaps I had in years past and was pushing the car towards it's limits.
Got to say I'm terrified at the idea of messing about with the car's suspension. Apologies as I know this is a little clichéd bu: Surely M engineers are paid a lot and exeprienced to sort it. No way I can see how just new springs and bigger wheels would magically improve things unless for pure track driving. :fuelfire:
A good set of coilovers absorbs much better the bumps an holes. the rebound of the coilover is much quicker and so the car will be much more planted and less jumpy.
And of course the 19" when you look performance whise and ride quality whise, they are not the best setup for the Z4M.
i drove a z4m with 18" and a set of KW V3 over a day in Luxembourg and the difference to stock is just mindblowing. I really cant describe it. The ride is harder yes BUT no jumpy lumpy on the road it goes goes goes.
Then went back to my Z4M stock with 19 and wanted to change everything directyl. So sold my 19 and bought 18" Ultras.
An this Winter a set of coilovers will be on my car
And of course the 19" when you look performance whise and ride quality whise, they are not the best setup for the Z4M.
i drove a z4m with 18" and a set of KW V3 over a day in Luxembourg and the difference to stock is just mindblowing. I really cant describe it. The ride is harder yes BUT no jumpy lumpy on the road it goes goes goes.
Then went back to my Z4M stock with 19 and wanted to change everything directyl. So sold my 19 and bought 18" Ultras.
An this Winter a set of coilovers will be on my car
Hi,
Sounds like geo is out to me or tyre pressures
The z4m is firm, but I only found this an issue at lower speeds, at attacking speeds the car smoothes out. under braking the backend isn't turning to over take the front. what tyre pressure are you running?
I've just swapped the z4 for a CSL and it lacked the planted feeling until I restored the pressures back to the manufactures recommend psi.
I'd guess yours are too high with symptoms your describing
Sounds like geo is out to me or tyre pressures
The z4m is firm, but I only found this an issue at lower speeds, at attacking speeds the car smoothes out. under braking the backend isn't turning to over take the front. what tyre pressure are you running?
I've just swapped the z4 for a CSL and it lacked the planted feeling until I restored the pressures back to the manufactures recommend psi.
I'd guess yours are too high with symptoms your describing