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      10-21-2007, 03:46 PM   #103
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Drives: E92 M3
Join Date: Sep 2006
Location: San Diego, CA USA

iTrader: (1)

Throttle response

Originally Posted by lucid View Post
Are you sure about that? Press release says:

"A separate throttle butterfly for each cylinder - eight in this instance - is a feature adapted from BMW M's racing heritage and provides immediate reaction to the gas pedal at all times. Two stepper motors operate the four throttle butterflies on each row of cylinders, giving the engine a particularly sensitive response at low speeds together with an immediate reaction whenever the driver presses down the accelerator for extra power and performance."

Are you sure the different throttle response settings do not have something to do with how the motors are controlled and therefore respond to driver input--meaning there might be more than just a linear mapping in between the two? It is possible that there is a response rate that cannot be achieved no matter how hard you push on the pedal unless the system is in the sport plus setting.

This would be good to know because if you are right, MDrive simply boils down to the M button (as long as you are okay with taking DSC offline), and I'd probably give up the M button in order to avoid the double hump.
The "extra power and performance" line is pure hogwash, certainly wrt "power". No matter how a throttle mapping is set no pedal force = idle and fully depressed pedal = full throttle. The mapping controls the linearity of the butterfly response vs. pedal travel as well as the speed of butterflys vs speed of pedal. That being said it may be as you stated that Sport Plus setting offers a mapping speed not obtainable by a human. But again, that being said I think the result is still not ultimate performance, rather feel and control. It would be an interesting experiment to find two closely matched cars and drivers and do a rolling start test with the throttle in different modes. This can be done now with an E46 M3 as well.