Originally Posted by Thumperx
It's definitely NOT a placebo. Bottomline, it depends on what you are after in suspension set-up. If you're looking for a true GT ride and set-up; meaning, the suspension design is comfortable daily ride and then handles very good at the track. Applying the M3 front bits is a first positive step. Or are you looking for a track setup, then you have much more to go.
Changing the front to M3 bits (more negative camber and firmer bushings), you may find great turn in (greater amount of driver's feedback). But soon you may find unwanted recklessness at the rear due to the softer bushing links and sub-frame bushings.
This may be the reason why the current M3 is so great because it a well balance and provides a higher level feedback. Once you tamper with one area, you may find yourself spending a lot of time (at least for myself) sorting out the other area/s. Ex: do I need to install the sway bars?
Softer springs provide a comfortable daily ride. But not so good when driving at the track due when certain amount of inertia forces act on front and rear weight transfer. Firmer springs is then desired. Not so great on the street (coil over). I kept my sport springs and beefed up all the other areas. I'm extremely happy with the out come, and my wife is even happier.
There is far more info to do, like others have mentioned, continue searching.
Well said Thumperx ! I decided on the Dinan springs and that really stiffened up the ride - so much so that my wife gets car sick now on trips lasting even just an hour. We can't take the car on trips now.
Decide what you want in the car - what your major percentage of driving is. If you want a race and track machine, you can build it - but it comes at a cost.
if you want much more performance and handling then do what Thumperx and others have done - but do the M3 arms (front/rear) and I would put in camber plates too for additional turn in and front end grip. If you are going with bigger rims/tires, REMOVE some or ALL of the stagger. This will give you an amazing handling machine, good ride (with non RFTs by the way).
THere is no substitute for reading, reading and reading on this forum. you have to do your homework.
2008 335i E92 Black, Procede Rev 2.5 (11-1 map), BMS DCI, AR Catless DPs, AMS FMIC, Procede PWM Meth, Forge DVs, CDV delete, 230s w/ 235/265 Michelin PSS, Dinan S3 susp w/ front/rear M3 arms (4), Wavetrac LSD, Subframe bushings, Dinan Rear Sway, Rogue toe arms, Stoptech Slotted rotors, Stoptech Street pads w/ steel lines