Great thread containing a wealth of info from people who have lots of experience and knowledge concerning aftermarket suspension set ups. I have a question. I'm about to install a set of H&R coil-overs. I do not track my car but am looking to improve my street performance. Do I need to do anything else while I'm doing the coil-over install? Like rear shock mounts, camber plates, etc? Appreciate your input.
Your experiences of aftermarket suspension on the Z4 MC
- Thread starter exdos
- Start date
H n R are a great option, their price simply CANT be ignored.... really nice option BUt... these are a street coilover, you have height adjustability, nothing else.... think about your aims for the car, track use??? i couldnt suggest these, their are similarly priced units that are PROPER track items (ground control) for street use im going to guess you may have better handling, but ultimately these should offer a sporty ride, with the added bonus of lowering the car to your requirement.
Camber plates are imo awesome, but again come with pitfalls, further NVH, possible noises and clunking, added stress to the suspension turrets (need to be reinforced).
i simply cant recommend the Re rear top mounts enough, you can change the dampers in 5-10 mins if you need to once you have these in place, they are very well made, and are compltely rebuildable!! i Special ordered poly inserts but id suggest neoprene is more than enough.
in terms of you choice for suspension look at your aim? road, track, or maybe both?? mine is abit of both but i went for a track orientated setup. For me its providing what i want. For a completely DD setup... no way in a million years would i have choosen the units i did.
hope this helps.
Camber plates are imo awesome, but again come with pitfalls, further NVH, possible noises and clunking, added stress to the suspension turrets (need to be reinforced).
i simply cant recommend the Re rear top mounts enough, you can change the dampers in 5-10 mins if you need to once you have these in place, they are very well made, and are compltely rebuildable!! i Special ordered poly inserts but id suggest neoprene is more than enough.
in terms of you choice for suspension look at your aim? road, track, or maybe both?? mine is abit of both but i went for a track orientated setup. For me its providing what i want. For a completely DD setup... no way in a million years would i have choosen the units i did.
hope this helps.
As has been said above, from the outset you need to know exactly what you are trying to achieve in order to get there. When you say you want to improve street performance, what is it that you find wrong with the OEM suspension and set up which makes you want to change it? Why have you opted for H&R coilovers and have you first hand experience of this suspension on a Z4MC? Are you doing the installation yourself?
Before installing the suspension, make a good note of the existing ride height at each corner, and when adjusting the height of your new kit, make sure you drop by the same amount at each corner. I know a lot of people like the "slammed" look, but it doesn't always improve the handling even though it lowers the centre of gravity of the car. Make sure that you keep the ride height "practical" so that you can drive the car around without risking damaging it on kerbs, sleeping policemen, sloping driveways etc.
Camber/castor plates can be very useful so that you can adjust the geometry to improve handling/performance. I think most people focus on the negative camber gains, but castor adjustment can actually achieve a dynamic negative camber gain without the need to increase static negative camber. It is possible to obtain camber/castor plates which have the bearings mounted in polyurethane (I have these on my Z3MC) which doesn't increase the NVH so much as solid plates. I believe Vorshlag make these for the Z4MC. I'm sure that you are already aware that you can adjust from camber a little by removing the locating pins in the front OEM top mounts, so it might be best to experiment with this before opting for camber/caster plates.
Rear top mounts which allow the dampers to be removed from inside the wheel arch are most useful and there are a few different makes, but Rogue Engineering top mounts are probably the best known. There's a cheaper alternative using BMW parts which I've described here: http://www.z4-forum.com/forum/viewtopic.php?f=9&t=38918&start=30 in my post dated 28th June 2012.
I can also recommend fitting a Rear trailing arm Limiter kit. There are 2 different types that I know of: Turner Motorsports and Rogue Limiter shims. These prevent the trailing arms moving laterally in their brackets, thus preserving rear geometry.
Getting the geometry set up right can also considerably improve handling as does ensuring that your tyres are at the optimum pressures.
Before installing the suspension, make a good note of the existing ride height at each corner, and when adjusting the height of your new kit, make sure you drop by the same amount at each corner. I know a lot of people like the "slammed" look, but it doesn't always improve the handling even though it lowers the centre of gravity of the car. Make sure that you keep the ride height "practical" so that you can drive the car around without risking damaging it on kerbs, sleeping policemen, sloping driveways etc.
Camber/castor plates can be very useful so that you can adjust the geometry to improve handling/performance. I think most people focus on the negative camber gains, but castor adjustment can actually achieve a dynamic negative camber gain without the need to increase static negative camber. It is possible to obtain camber/castor plates which have the bearings mounted in polyurethane (I have these on my Z3MC) which doesn't increase the NVH so much as solid plates. I believe Vorshlag make these for the Z4MC. I'm sure that you are already aware that you can adjust from camber a little by removing the locating pins in the front OEM top mounts, so it might be best to experiment with this before opting for camber/caster plates.
Rear top mounts which allow the dampers to be removed from inside the wheel arch are most useful and there are a few different makes, but Rogue Engineering top mounts are probably the best known. There's a cheaper alternative using BMW parts which I've described here: http://www.z4-forum.com/forum/viewtopic.php?f=9&t=38918&start=30 in my post dated 28th June 2012.
I can also recommend fitting a Rear trailing arm Limiter kit. There are 2 different types that I know of: Turner Motorsports and Rogue Limiter shims. These prevent the trailing arms moving laterally in their brackets, thus preserving rear geometry.
Getting the geometry set up right can also considerably improve handling as does ensuring that your tyres are at the optimum pressures.
daz05 said:
absolutely agree... sadly most peoples reasons for getting coil-overs is to simply lower the car. this particular unit is one of the more popular choices..... does it translate to a better handling car??? hmmm subjective.... that said i read nothing but good stuff about H & R coil-overs, but how much better than stock would they be.... for me stock on a smooth track were pretty freaking good! only the power onslaught really showed them up in the end.
slammed car... imo means jack shite and often leads to a poorer handling ROAD vehicle....
best bang for buck HAS to be the ground control track coiovers, YOU choose the springs rates, YOU choose the type of damping you want, and its rebound adjustable.... the ONLY issue i have with ground control is, a search shows lots of issues with products and more importantly customer service, but for 1500 quid im pretty certain you'll get as good as you can get performance from them... certainly right up their with the clubsports, nitrons, AST, ect ect, choose a lowish spring rate, GC use proper linear springs as well, and theirs no reason you cant have a nice road car too!!
http://imageshack.us/photo/my-images/440/204575fs.jpg/
Appreciate the input gents... As I said before, I don't track my car, so my goal is to achieve some lowering (I l happen to like the look), while at the same time realizing some improvement in street performance (less body roll, better shock absorption, etc). There are numerous favorable posts by members of this forum and others suggesting that the H&R coil-over set up is capable of delivering just that "have your cake and eat it too" result. Since the price for parts and installation (Vivid Racing in Gilbert AZ is doing the work) is fairly reasonable, I've decided to give it a try. On your recommendations, I'm also having them install a set of Rogue Engineering rear shock mounts. My appointment is this coming Friday and I'll report my impressions back to this thread.
Update: H&R coil overs (ride height lowered 1 inch) and Rogue Engineering rear shock mounts were installed this past Friday (9/14) by Vivid Racing in Gilbert AZ http://www.vividracing.com/catalog/index.php. So far, I'm absolutely delighted with the results! My objectives were to 1) improve street performance, 2) lower ride height, 3) retain ride quality and 4) not spend a fortune. While I've not yet had a chance to fully test the car's performance, early indications are that it is improved. Ride height has been lowered one inch (I'll wait a couple weeks for the springs to settle before deciding whether to lower more). Ride quality is surprising great! And, IMO, the total spend was quite reasobable... about half the cost of the KW v3 setup. Thanks to dubseed and others for their favorable reviews of the H&R coil over setup which I too would strongly recommend for anyone looking to acheieve the non-track objectives outlined above.
Beedub said:
This pic does a better job of showing how much the car has been lowered. There's still about 3/4" adjustment left in the H&R coil overs to take it down further, but I think I like it where it is. Interestingly, before lowering, I had a little rubbing on the left front wheel well liner at full turn, but now that is gone because the rub point is below the maximum arc of the tire.
I think thats about the right height, any lower and you will be catching all over the place!jrainlay said:Beedub said:
This pic does a better job of showing how much the car has been lowered. There's still about 3/4" adjustment left in the H&R coil overs to take it down further, but I think I like it where it is. Interestingly, before lowering, I had a little rubbing on the left front wheel well liner at full turn, but now that is gone because the rub point is below the maximum arc of the tire.
Looks sweet! Has this set-up resolved the over firm rear damping issue of the stock car in your opinion?
original guvnor said:jrainlay said:Beedub said:
This pic does a better job of showing how much the car has been lowered. There's still about 3/4" adjustment left in the H&R coil overs to take it down further, but I think I like it where it is. Interestingly, before lowering, I had a little rubbing on the left front wheel well liner at full turn, but now that is gone because the rub point is below the maximum arc of the tire.
Looks sweet! Has this set-up resolved the over firm rear damping issue of the stock car in your opinion?
Good question - I'd love to know too
Franzino said:
I'm assuming that you're referring to the ACS Racing suspension here. If so, you'll need to check that with ACS directly. It seems that so few Z4M owners go for aftermarket suspension, so all the different swap combinations between the Z4M and other cars haven't yet been tried.
Hi chaps, I have recently acquired an H&R coilover setup and whilst I do track my car and wanted a fully adjustable set, at the price point I got them for I couldn't say no. I am currently running stock dampers with Eibach springs so will be interesting to see what improvements they bring.
Hope to have them on by the end of Jan and will be out on track in Feb so will report back with my findings.
Fingers crossed they offer some improvement...
Sent from my iPad using Tapatalk HD
Hope to have them on by the end of Jan and will be out on track in Feb so will report back with my findings.
Fingers crossed they offer some improvement...
Sent from my iPad using Tapatalk HD
john, found some interesting info for your browsing...
seems BMW specc'd the m3 GTS with Kw clubsports!!! very cool info and pics here...
http://www.m3post.com/forums/showthread.php?t=385970
Whats not so good is every article ive read about the GTS said great on track, back breaker on the road, too uncompromising :-( LOOOOL!!
i guess the best setup is like the new mp4 12c with its hydraulic setup.......
seems BMW specc'd the m3 GTS with Kw clubsports!!! very cool info and pics here...
http://www.m3post.com/forums/showthread.php?t=385970
Whats not so good is every article ive read about the GTS said great on track, back breaker on the road, too uncompromising :-( LOOOOL!!
i guess the best setup is like the new mp4 12c with its hydraulic setup.......
Byron,Beedub said:
That's interesting that they've gone for KW. I've had a read of those links. It's quite right that a car like the M3 GTS should have adjustable suspension and it should've been an option on all the ///M cars since the M3 CSL.
If I had Clubsports, I'd be experimenting with the soft end of the damper settings for street use. You can put up with hard settings on track when your concentration is devoted to going as fast as possible and you're not thinking of comfort.
Those Clubsports are sooooooo much simpler to adjust than the KW V3s. The beauty of adjustable suspension is their Jekyll and Hyde "personality" and being willing to switch between soft and hard as and when necessary. The handling with soft damping but with the correct spring rate on bad A&B roads is way better than stiff damping with the wrong spring rates.
In one of the links here: http://www.insideline.com/bmw/m3/2011/2011-bmw-m3-gts-first-drive.html from the links you've given, it states: "With the use of wheel spacers and forged-aluminum 19-inch wheels, the GTS has wider tracks than the stock M3." It's interesting that BMW have seen fit to use wheel spacers. I've always thought that they improve handling and have no drawback provided you use hubcentric spacers.