What does the M button really do in technical detail?

[v1k0d3n]

I've searched around. I know that the M button creates "sharper response", and there's no doubt on this, but what does it really do? Increase fuel? So does this impact fuel costs from what you can tell (for those who use it a lot)? Does it increase turbo PSI? My STi did this, and it was completely silly because their "Intelligent" mode was actually LESS fuel efficient, because by nature Turbo's are more fuel efficient (so I always left it in S# mode). Does it increase timing slightly? From a technical overview...how does this work? Thanks in advance.

[MusclezMarinara]

Originally Posted by v1k0d3n

I've searched around. I know that the M button creates "sharper response", and there's no doubt on this, but what does it really do? Increase fuel? So does this impact fuel costs from what you can tell (for those who use it a lot)? Does it increase turbo PSI? My STi did this, and it was completely silly because their "Intelligent" mode was actually LESS fuel efficient, because by nature Turbo's are more fuel efficient (so I always left it in S# mode). Does it increase timing slightly? From a technical overview...how does this work? Thanks in advance.

Check the manual?

All I know thus far is sharpens throttle response.
Turbos stay the same the car has the Overboost function

[MDORPHN]

The 1M has a drive-by-wire throttle, not a mechanical linkage.

The M button simply changes the programming so the throttle opens more quickly as the throttle is pressed down.

Neil

[josephvman]

I think it just sharpens the throttle response, as far as I can tell. My Ducati Multistrada 1200S has the same kind of setting, either a faster or slow throttle. It would be nice if the "M" button would raise the stability control threshold for less intrusion, instead of having to push the button, and then the stability control button everytime I get in the car.

[Plaz]

I really wonder if throttle pedal recalibration is all it does. 100% in "M" mode feels more powerful to me than 100% in non-M mode, according to my seat-of-the-pants-o-meter.

[v1k0d3n]

Originally Posted by Plaz

I really wonder if throttle pedal recalibration is all it does. 100% in "M" mode feels more powerful to me than 100% in non-M mode, according to my seat-of-the-pants-o-meter.

I've heard statements that it increases tq...so I'm not sure if it's just throttle "response". i had a Suzuki GSXR 1000 and it had the "3 settings" as well, but this was done via fuel mappings (until I had the thing mapped for track-only use). they were very clear. how do you increase tq with throttle response? this is why i posted the question...

Also, is it ok to leave this button pressed "on" all the time? Can I set this so that it stays "on" when I turn off/on the car? Is there a difference in fuel consumption?

Reference: http://www.motorward.com/2010/12/bmw...ally-revealed/

"Like other M-powered cars, the 1M Coupe features an M button, an electronically-controlled overboost function to briefly increase torque under full load by another 37 lb-ft (50 Nm). This temporary torque peak of 369 lb-ft gives the car a substantial increase in acceleration. We still think it’s wrong, why the car isn’t in M mode all the time? Who would want to deliberately reduce his car’s power?!

With the M button pressed, the car goes from 0 to 60 mph in just 4.7 seconds (0-100 kmh in 4.9 seconds). The standing quarter-mile mark comes up in 13.2 seconds. Top speed is limited electronically to 155 mph (250 kmh)."

[MDORPHN]

Originally Posted by v1k0d3n

I've heard statements that it increases tq...so I'm not sure if it's just throttle "response". i had a Suzuki GSXR 1000 and it had the "3 settings" as well, but this was done via fuel mappings (until I had the thing mapped for track-only use). they were very clear. how do you increase tq with throttle response? this is why i posted the question...

Also, is it ok to leave this button pressed "on" all the time? Can I set this so that it stays "on" when I turn off/on the car? Is there a difference in fuel consumption?

"Like other M-powered cars, the 1M Coupe features an M button, an electronically-controlled overboost function to briefly increase torque under full load by another 37 lb-ft (50 Nm). This temporary torque peak of 369 lb-ft gives the car a substantial increase in acceleration. We still think it’s wrong, why the car isn’t in M mode all the time? Who would want to deliberately reduce his car’s power?!

With the M button pressed, the car goes from 0 to 60 mph in just 4.7 seconds (0-100 kmh in 4.9 seconds). The standing quarter-mile mark comes up in 13.2 seconds. Top speed is limited electronically to 155 mph (250 kmh)."

Motorward is plain wrong. The M button does nothing but change throttle response.

Neil

[v1k0d3n]

Originally Posted by MDORPHN

Motorward is plain wrong. The M button does nothing but change throttle response.

Neil

I completely disagree. More research (and hence, why I asked the question):

From BMW M Engineer J. Schwenker:

"Q: Why does the already good responsiveness of the engine improve noticeably when the M button is pressed?

JS: The M button leads to an emphatically sporty engine control with the focus clearly on the response characteristics of the engine. Comfort-related issues such as smooth running are dealt with on a secondary basis.

Q: What is the precise difference between the two available motor mappings?

JS: On the one hand, the focus of basic coordination lies on unlimited everyday use, while on the other hand, the car’s sporty character is to be allowed to develop. Different motor mappings were implemented in order to achieve these two opposing requirements: from spontaneous and snappy to harmonious, long-haul capabilities. Thus, for example, passengers find the jerking of the head caused by the spontaneous response of the engine when accelerating and decelerating to be quite uncomfortable. The driver registers this less than his passengers. This effect is greatly reduced through basic coordination."

So it's "motor mappings". Now...for a more technical answer...I'm trying to find out what those "mappings" are, what they're doing and how it will impact everyday use/fuel consumption.

I think his answers are kinda BS if you ask me. I want a little more detail than "we don't want passengers getting jerked around" by the drivers who want to drive like PacBMW techs.

[MDORPHN]

Originally Posted by v1k0d3n

I completely disagree. More research (and hence, why I asked the question):

From BMW M Engineer J. Schwenker:

"Q: Why does the already good responsiveness of the engine improve noticeably when the M button is pressed?

JS: The M button leads to an emphatically sporty engine control with the focus clearly on the response characteristics of the engine. Comfort-related issues such as smooth running are dealt with on a secondary basis.

Q: What is the precise difference between the two available motor mappings?

JS: On the one hand, the focus of basic coordination lies on unlimited everyday use, while on the other hand, the car’s sporty character is to be allowed to develop. Different motor mappings were implemented in order to achieve these two opposing requirements: from spontaneous and snappy to harmonious, long-haul capabilities. Thus, for example, passengers find the jerking of the head caused by the spontaneous response of the engine when accelerating and decelerating to be quite uncomfortable. The driver registers this less than his passengers. This effect is greatly reduced through basic coordination."

So it's "motor mappings". Now...for a more technical answer...I'm trying to find out what those "mappings" are, what they're doing and how it will impact everyday use/fuel consumption.

I think his answers are kinda BS if you ask me. I want a little more detail than "we don't want passengers getting jerked around" by the drivers who want to drive like PacBMW techs.

You may be right, but -- based on the interview with the BMW engineer -- I'm not sure that the difference in mappings amounts to anything more than throttle response.

Very interested in whatever your research uncovers.

Neil

[v1k0d3n]

Originally Posted by MDORPHN

You may be right, but -- based on the interview with the BMW engineer -- I'm not sure that the difference in mappings amounts to anything more than throttle response.

Very interested in whatever your research uncovers.

Neil

Saying (or repeating rather) increased "throttle response" is generic. Ok, I agree with you (never doubted)...increased throttle response. But let's liken throttle response to the color Blue. Now I'm asking is this Blue more of a sea-blue, or more of a baby-blue. HOW is throttle response achieved? That is the question.

[MDORPHN]

Originally Posted by v1k0d3n

Saying (or repeating rather) increased "throttle response" is generic. Ok, I agree with you (never doubted)...increased throttle response. But let's liken throttle response to the color Blue. Now I'm asking is this Blue more of a sea-blue, or more of a baby-blue. HOW is throttle response achieved? That is the question.

Uh... maybe different mapping

Neil
(a might colorblind)

[robertm]

I think the throttle response should be likened to the color orange. Everybody knows its much faster than blue. Even sea blue..

[b33g33]

Originally Posted by robertm

I think the throttle response should be likened to the color orange. Everybody knows its much faster than blue. Even sea blue..

If you drive away fast enough, even the black car will appear to be VO..

http://en.wikipedia.org/wiki/Red_shift

So, it's actually the other way around. The more you floor that pedal, the more orange your 1M.

[v1k0d3n]

Originally Posted by b33g33

If you drive away fast enough, even the black car will appear to be VO..

http://en.wikipedia.org/wiki/Red_shift

So, it's actually the other way around. The more you floor that pedal, the more orange your 1M.

haha! ok...so maybe my "Blue" bad example.

thought about it more. so you're saying that all it is, is that the fly-by-wire pedal has been retarded...and that's it? someone else said that 100% to 100% M on/off and M on felt stronger. another good way of testing is hit the M button while accelerating and see if that does anything (while it's going through the RPM).

[JimD]

I haven't driven the 1M (yet) but I've driven the M3, M5 and M6 with the M button depressed. On all the Ms I have driven, the M button also reduced the intrusiveness of the stability control. It kicks in when you are a little less under control (in its opinion). I got a M3 sideways on the PC track in M mode, for instance. That should not be noticable on the street but is nice on the track. I would bet the 1M button also affects the stability control. It may not do much more than just pressing the stability button once, however.

Jim

[Fundahl]

I could see maybe the delay or "gain" on the butterfly valve to be adjusted and possibly "overboost" only happens with the M button on.

I'll find some more clues when I do some JB4 datalogs.

[///M1]

Just think of it as a more advanced Srintbooster

http://www.sprintbooster.us/

[clived]

Originally Posted by v1k0d3n

So it's "motor mappings". Now...for a more technical answer...I'm trying to find out what those "mappings" are, what they're doing and how it will impact everyday use/fuel consumption.

Except it isn't "motor mappings" is it. There is no way a German engineer said "motor mappings". Given the poor quality of the rest of the translation, I suspect you'd find if you looked at the interview in original German, and got a good German and English speaker for a less literal translation, it would be much clearer what he meant.

[Pugland53]

The M button alters the throttle response as mentioned already, but also alters the DSC+ to allow more wheel slip than non M mode.

[clived]

Originally Posted by Pugland53

The M button alters the throttle response as mentioned already, but also alters the DSC+ to allow more wheel slip than non M mode.

Do you have any evidence of that? That's what MDM mode does (well, it's part of what MDM mode does) and the M button does not invoke MDM mode. I certainly have not observed any greater allowance of wheel slip in M mode - have you?

[bdaddylo]

Originally Posted by Pugland53

The M button alters the throttle response as mentioned already, but also alters the DSC+ to allow more wheel slip than non M mode.

You don't have a clue, do you?

[bdaddylo]

Originally Posted by ///M1

Just think of it as a more advanced Srintbooster

http://www.sprintbooster.us/

+1