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      06-18-2008, 10:39 AM   #32
Major General
lucid's Avatar

Drives: E30 M3; Expedition
Join Date: Apr 2007
Location: USA

iTrader: (0)

Originally Posted by GregW / Oregon View Post
"EDC-K is available for the first time in the E92 M3. EDC-K is an option and is based on the EDC-K in the E65.

Both dampers of one axis are always activated in parallel. The valve is installed internally in the damper in the damper oil system.

The driver can choose between three settings, the controlled programs "Comfort" and "Normal", or the uncontrolled fixed setting
"Sport". The program is selected using the EDC-K button on the center console or preset via the MDrive menu and activated using the M button on the steering wheel.

The input signals come from two vertical acceleration sensors in the front wheel arches and a third sensor in the rear right-hand wheel arch.
The steering column switch cluster sends the steering angle to the F-CAN. This is transmitted together with the wheel speeds from the DSC to the PT-CAN and evaluated in the EDC-K control unit.

The longitudinal, lateral and vertical accelerations calculated as a result are used as a basis for regulation. The EDC-K button signal enters the junction
box and is transmitted to the EDC-K on the PT-CAN." -- BMW Aftersales Training - Product Information

The only thing that is controlled is the shock damping, both compression and rebound. The following graph illustrates the damping force on the vertical axis "A" (compression below & rebound above) related to the damper piston speed on the horizontal axis "B". Controlling ride height would take some sort of air suspension or such. Also, the M3 does not have active anti-roll bars like the Range Rover and some other vehicles. Still, it is quite effective.
Thanks for the info Greg. You always come up with solid specs when needed.