SMGII Shift Time Variation

[Kaisake]

Some information on the varying shift times (80ms being the lowest) due to a number of variables.


"I’m with BMW of North America, LLC. The shifting time of the SMG in the M3 varies according to different factors, i.e. engine speed, torque, steering angle signals and road conditions. The control module gathers input from 11 different sensors to determine the speed of the shift. These sensors are outlined in the picture below.

In the sequential mode, the speed of the shift and the clutch actuation both depend on the selected program. Of the 6 sport mode programs S6 is the most aggressive. S6 can only be accessed with the Dynamic Stability Control turned off and offers the shortest possible shifting time, which can be as low as 80 milliseconds.

Based on the input of the sensors, the shifting time of the SMG is determined to match the following:

1. Best torque-power flow (from the engine to the transmission).
2. Minimum wear of the components.
3. Vehicle safety (SMG will alter clutch actuation to prevent wheel slippage).

If you have any questions, you can call us at 800-831-1117."





Source: (http://bimmer.roadfly.org/bmw/forums...3480320&page=1)

[Zeviticus]

good info...

...a thought, would it be possible to hook an SMG 6-speed to a 96-99 M3? Would it be too costly or difficult to connect the whole computer system?

[Ximian]

Very nice information, a friend was actually asking me about this earlier, provided some good information for him.