non M Coupe suspension refresh?

[jmilt13]

I would like to start collecting parts for a suspension refresh on my 07 e86 non M.

Looking for advice on which parts are definitely needed and which are optional.
Do I need to replace all bushings?

I plan on doing control arms/bushings.

I also plan to replace struts. Do I need to replace the springs as well?

Is there any advantage to going with coilovers over stock struts/springs? I'm happy with the ride height (M sport suspension with M wheels). I'm not going to track it and want to maintain any ride comfort possible.

Should I also replace trans/engine mounts? Do they wear out?

Thanks for any advice

[belcom]

There are many options for replacement. Coilovers are good in a sense that you can control at least the height and with more advanced options also compression and rebound.

For a street car I've personally had KW v1 before and now have ST X (made by KW and basically very similar to V1) on the roadster and in my opinion these are a great option. They're firm but yet comfortable and ride really good. Its a sports car after all, not a luxury boat lol. ST X are height adjustable only and spring rates and shock valving are perfectly matched specifically for the vehicle application. If you keep the height reasonable the comfort level will be excellent. In my experience they do require 2k or so to fully break-in and feel the best. Right off the bat will be a bit stiff.

You can also do something like Bilstein B6 or B4 shocks or Koni Yellow and keep your original springs but the rear springs seem to have a tendency to break. Probably a good idea to replace rear springs in that case as well. Don't believe the fronts have that issue.

I'd also replace FCABs, RTABs (put RTAB limiters as well), front shock mounts (stock BMW ones are cheap enough), rear shock mounts (Rogue is a good option), add front/rear reinforcement plates (fronts are from e46 M3 and rears can be bought from various companies including Rogue). Check the sway bar links for play and sway bar bushings as well.

As far as control arms I'd say check them thoroughly first. If there no ball joint movement and they're not bent why replace? Just ride them out until they do fail. Check every year or after certain mileage.

I would do some research on coilovers and spring/shock combos and see what people say about it. From your research results you should be able to derive what will work best for you personally.

Also, do check your tie rods, If there's play, replace. Don't forget alignment after all said and done (very important to dial it in).

After the refresh it will ride super nicely and so much more exciting and engaging.

[Ivesy]

I'm in exactly the same boat. I have bought a car that has stance coilovers and it handles horridly. I'd like to reset to Oem springs with bilstein b6 as have read an article from Birds (UK bmw specialist) who recommend this setup. Only problem is finding the correct part number for 3.0si coupe springs. Any help welcome. T

[Steeler]

Originally Posted by Ivesy

I'm in exactly the same boat. I have bought a car that has stance coilovers and it handles horridly. I'd like to reset to Oem springs with bilstein b6 as have read an article from Birds (UK bmw specialist) who recommend this setup. Only problem is finding the correct part number for 3.0si coupe springs. Any help welcome. T

Several to choose from.
OEM #'s included.

https://www.ecstuning.com/BMW-Z4-3.0...n/Springs/OE/2