Suspension Overhaul
- Thread starter ChillZ4
- Start date
I don't know the exact percentage change, but that's why I bought Eibach - a name I trust and hence don't need to know that info. They've got general advertising points that they're stiffer, and going on positive reviews of them, that's enough for me to know.Mr Whippy said:
a11y said:
But BMW actually made the car, and tuned EVERY single aspect of that suspension to every other part... surely that is enough for you to know
The fact you can't get a set of same ride height springs, to me, suggests their target is people lowering cars, not actually trying to offer an improved handling package.
The idea that we should also just trust them to not need to know the specs is a worrying way to go. I trust BMW because they made the car, the springs, the dampers, the bump stops, the bushings, the wheels, chose the alignment specs, the king pin and castor angles, the tyre pressures, ackerman etc, yet Eibach just make four new curly bits of metal and improve on the BMW package?
I'm a negative person when it comes to all this as you can see. Unless someone can show me WHY their stuff is better, then I don't think they actually know WHY it is better, or simply know it isn't any better. I just think you lose 15mm of bump space, and get worse matched dampers when you actually need them (ie, when pushing on hard and get some mid-corner bump energy un-controlled by an underdamped system, yikes)
But, it looks lower, and apparently better, yay
(each to their own and all that, just when people do it and are sold on the idea that it's better when it's probably actually worse, ie, K&N warm air induction kits)Paying good money for a handling downgrade, just so it looks better
Dave
Some people just prefer the lower stance, this to some is more important!
But on the point that you trust BMW, etc...
Well buying some Eibach springs isnt exactly a move that will definately make the car handle worse, I mean Eibach has have years of experience perfecting the manufacturing of springs! Also, they do test the springs with the car!
But on the point that you trust BMW, etc...
Well buying some Eibach springs isnt exactly a move that will definately make the car handle worse, I mean Eibach has have years of experience perfecting the manufacturing of springs! Also, they do test the springs with the car!
Z4play said:
Did you also change out the springs? I also have the non-sport, and to my surprise there is not an ounce of compliance in this suspension. I'm not looking to turn it into a Cadillac, but a little bump absorption would be a novel trick considering I'm driving on some of the worst roads imaginable. Wife works in the same company and she had to come to my location one day so I drove her in. She actually was sick by the time we got to work.
Whippy, I understand your concerns and can't argue with most of them. But to say that nothing improves the OEM setup because BMW designed it is hard to believe. I've never once read a positive review of the Z4 suspension, so they obviously messed up somewhere.
Why won't Koni release FSD's for the Z4?
t20lau said:
Yep, if you have to have it lower, then that is a worthwhile reason for buying them.
I'm not sure what Eibach do to the setup. They offer no information except that they lower the car another 15mm ontop of the sports setup (just 15mm lower)
I don't doubt they can make physically good springs
It's just hard to know what you are buying into. It just feels so wrong for them to offer this and then also try suggest the setup is better than BMW's, despite not changing BMW's shocks, geometry, bushings etc. How could BMW have got it so right with all those bits, but just made the springs wrong?
Assuming they do do a good kit, why don't they market it with any kind of information at all? With brake pads we can review the compromises and benefits, or with engine mods we get dyno printouts and so on. But with suspension kits like this, we just get 15mm drop, but no information about the handling balance change, is it stiffer, a worse ride but better control?
That is what puts me off all these generic kits. I'd buy Intrax as they offer camber kits and very good dampers and then setup the car to my specific tastes, but I'd need to know what was wrong with what I had to start with, before I could make any changes and know what I ended up with was what I wanted.
Starting with a setup I didn't even understand on road and track at the limits, and then tampering with it by buying parts of an unknown quantity, I may as well just stab around in the dark, or, ultimately, leave it alone.
If you must lower, then lower away...
(just a personal bugbear that people buy cars and lower them within a few weeks having not even taken the car on a track or pushed them hard enough to even know the suspension is lacking for them, doing it purely to lower the car for 'looks' but then telling everyone it now corners flatter and so handles better (when it probably doesn't at all))
Sorry, had to get that out. I'm all up for modding/tuning but being realistic about why it's been done. Ie, I've done the sound generator mod because it sounds fapping ace. If it lost 5bhp I'd probably still leave it as is, and I'd admit I took sound over performance
Topshelf said:Z4play said:
Did you also change out the springs? I also have the non-sport, and to my surprise there is not an ounce of compliance in this suspension. I'm not looking to turn it into a Cadillac, but a little bump absorption would be a novel trick considering I'm driving on some of the worst roads imaginable. Wife works in the same company and she had to come to my location one day so I drove her in. She actually was sick by the time we got to work.
Whippy, I understand your concerns and can't argue with most of them. But to say that nothing improves the OEM setup because BMW designed it is hard to believe. I've never once read a positive review of the Z4 suspension, so they obviously messed up somewhere.
Why won't Koni release FSD's for the Z4?
Yes. I changed the springs first, without changing the struts, that's when I found the ride bouncy. I then changed out the struts and while I was at it, I changed the rear strut mounts. I have always found the ride harsh, but being a roadster I want to feel the road.
Z4play said:
Yeah both my '04 3.0i and my friend's 3.0i had sport suspensions and sport dampers, yet we still found the ride bouncy. I can't imagine how much worse it'd be putting the Eibachs on non-sport dampers.
And like I said obviously some people are not capable of discerning the differences. And what do I care. It's not my car and it's not my money. If one wants to put his wallet on the line and do the trials and errors himself, hey more power to him.
Yes. The Z is definately not a smooth riding sports coupe or sports sedan. It is what it is, a roadster meant for feeling and experiencing the road. I don't know if anyone can say that changing springs and the struts improves the ride comfort. I changed out the suspension purely for looks.
Z4play said:
Plenty of people have experienced improved ride comfort after going with aftermarket springs and Koni shocks or coilovers. It's not entirely the springs that cause the jarring ride. Stock dampers that have poor valvings are the bigger culprit. At full soft my TCK coilover set-up with Koni struts/shocks (valved to TCK's specs) ride more comfortable than stock. I've stiffened it up a bit and now I'd say it rides about the same as stock (maybe Rick Hunter can chime in and offer his opinions as he's driven my M a few times with my current slightly stiffened up setting). When I want to push the car harder, I stiffen up the settings even more, and/or put my spare stiffer rear springs on the car.
What's the rebound settings on your Z4?
Also, 19" wheels don't help ride comfort. There's a very noticible differece between 18's and 19's. Anyone who tells you he can't feel the difference is either clueless that he doens't know what he's talking about or lives somewhere where it has butter-smooth roads.
I have both 18" BBS RGR's and 19" BBS RGR's. If there's no difference in ride comfort i wouldn't be having such a huge dilemma deciding whether to put the 18's on my M for better ride comfort or the 19's for pure looks. It sucks that I can only have one set of wheels on my M at a time. So I swap them every other week for the hell of it.
I have both 18" BBS RGR's and 19" BBS RGR's. If there's no difference in ride comfort i wouldn't be having such a huge dilemma deciding whether to put the 18's on my M for better ride comfort or the 19's for pure looks. It sucks that I can only have one set of wheels on my M at a time. So I swap them every other week for the hell of it.
I've tried out a couple of roadys since I bought my car and I do agree that GP20's setup is comparable to stock. On 18's (with taller tire profile), his car rides very smoothly yet doesn't lose much road feel. That being said, though, I still find it's a tad soft for me. I think it's probably because I'm used to my coupé setup which is stiffer from the start. :idunno:
One great thing about GP20's setup is that it's adjustable. I wish I could have that for the days I don't feel hardcore.
Hey, GP20, you should try out 18"F, 19"R just for s#!ts & giggles
One great thing about GP20's setup is that it's adjustable. I wish I could have that for the days I don't feel hardcore.
Hey, GP20, you should try out 18"F, 19"R just for s#!ts & giggles
Is there any difference in the struts between European and North American versions as there seems to be a definate split on opinion as to the effectiveness of after market springs on standard / sports suspension.
From what I can find there are different part numbers for before and after 2005 whether this makes a difference or not.
Until 24/042005
Front Left Standard 31 31 6 761 893
Front Right Standard 31 31 6 761 894
Front Left Sport 31 31 6 761 895
Front Right Sport 31 31 6 761 896
Rear Standard 33 52 6 764 000
Reart Sport 33 52 6 796 001
From 25/04/2005
Front Left Standard 31 31 6 770 343
Front Right Standard 31 31 6 770 344
Front Left Sports 31 31 6 770 345
Front Right Sports 31 31 6 770 346
Rear Standard 33 52 6 770 342
Rear Sports 33 52 6 770 347
From what I can find there are different part numbers for before and after 2005 whether this makes a difference or not.
Until 24/042005
Front Left Standard 31 31 6 761 893
Front Right Standard 31 31 6 761 894
Front Left Sport 31 31 6 761 895
Front Right Sport 31 31 6 761 896
Rear Standard 33 52 6 764 000
Reart Sport 33 52 6 796 001
From 25/04/2005
Front Left Standard 31 31 6 770 343
Front Right Standard 31 31 6 770 344
Front Left Sports 31 31 6 770 345
Front Right Sports 31 31 6 770 346
Rear Standard 33 52 6 770 342
Rear Sports 33 52 6 770 347
Thanks for the input guys. I'm not doing anything right now as I'm still waiting to find out if I'll be employed in a few weeks. (Yay economy :x ) But I do plan an making a change down the road. Just trying to get some info as to whether it's worth the investment. Any non M coupe owners in PA/NJ with aftermarket suspension want to give me a test drive?
I am sorry to unearth this old thread. I was wondering if we could swap the lower control arm of a non m zed with that of an M. those on the M are the same as that found on a 330 e46 sport package. I am not sure but I think the main difference is that they have a solid outer ball joint and nothing more. Also meyle in it's hd product range gives only one lower control arm for both sport and non sport package e46's. So according to the above mentioned they must be identical ( thus no geometry change). Can someone verify this please?