m suspension

[andrewd]

I just bought A 06 m r. I had it up on my rack and noticed there is a sticker on the lower control arms it says m only. and the rear trailing arms have a m cast into them dose any one know if these suspension is diffrent from the reg z4. I could see springs shocks and sways but the control and trailing arms.

[Thisisdudewhoru]

Yes it does.

[-c-]

yea actually the whole rear subframe is different and has differnt wheel offsets from other Z4's all the way down to the rear diff housing is also different and under body struts and well just about everything......belive me i know!

[Incompatible]

Previously posted a while back, IIRC The source for the article below is ZER Customs.

Extensive new engineering for BMW M

Starting with the Z4’s already excellent chassis engineering – Motor Trend commented in its May ‘05 issue that the Z4‘s “sport suspension and solid chassis make this car a thrill to drive on canyon roads“ – BMW M has endowed the Z4 M Roadster and Coupe with typical M modifications that further enhance handling and tailor the cars' road capabilities to M’s higher performance level.

Front suspension. While retaining the Z4’s basic concept – strut-type with forged-aluminum lower arms – the M engineers created an essentially new version with:
• A wider front track (by 0.5 in.)
• Newly configured lower arms, still of forged aluminum; more complex shape with open sections for lightness, similar to those of M3s
• New steering knuckles, bolted to the struts (saves weight, sharpens steering response)

Such changes, subtle yet deep-reaching, are – as good as the basic BMW model is – key to achieving the “beyond exceptional” reflexes of an M model.

Rear suspension. Though modifications to the Z4’s Central Link (multi-link) rear suspension are less extensive than at the front, they are significant. Among others, the following major M elements are shared with M3s:

• Rear subframe – larger and stronger; accommodates differential with M Variable Differential Lock
• Wheel bearings
• Central (longitudinal) Links
• Arrangement of anti-roll bar.

As at the front, these modifications sharpen handling capabilities.

Ride height and suspension calibration. Like the Z4’s sport suspension, that of the Z4 M Roadster and Coupe are set lower compared to the standard Z4’s setup. Unlike the Z4, however, the M versions get an all-around new calibration of springs, shock absorbers, anti-roll bars and bushings to BMW M parameters; this includes specific auxiliary springs at the front and rear.

A new steering system. BMW M has somewhat different priorities: a greater emphasis on absolutely accurate road feedback and ultra-spontaneous response to the driver’s commands at the steering wheel. In this context, higher parking
and low-speed efforts are acceptable. Thus M gave the Roadster and Coupe a hydraulically-assisted rack and pinion with a power-steering pump calibrated with assist characteristics optimized for the Z4 M Roadster and Coupe. This system reduces parking efforts somewhat, but not to the degree that vehicle-speed-sensitive assist does.

[andrewd]

I like it

[Z4Murder]

cool post^