MDM

[rye m3]

I've seen several posts suggesting driving with MDM active on the street was akin to inviting a crash. I've driven with it on in low traction situations, such as heavy rain and find the intervention very close to the traction control on a 997. It comes on, but doesn't come on right away. It lets you have a little power oversteer, but not too much. Porsche stability control is MUCH better than BMW ever was, but with the new system I think it getting much closer.

Anyone have similar experiences?

[gblansten]

I turn off MDM in the winter secondary to tire grip in the cold and I turn it off in general if it is raining.

[RudyP]

Eh - for the street, don't see much difference since I don't drive around with high slip angles except for very occasional situations (first snow of the year in a big parking lot for example). The stability control system on my 997.1 C2S is very good, however, I even leave it on on the track and find that it really does not slow me down (BMWCCA, PCA, etc instructor FWIW). I don't track my M3 but back when I tracked an E46 3er, I used to disable the traction/stability control because it was restrictive at times.

[mahmud///M]

My traction is always off. Rain, shine, cold road or hot. BMW has good chassis stability and great balance, so even if u lose it it's. Rey easy to bring it back.

[Ateam]

Originally Posted by rye m3

I've seen several posts suggesting driving with MDM active on the street was akin to inviting a crash. I've driven with it on in low traction situations, such as heavy rain and find the intervention very close to the traction control on a 997. It comes on, but doesn't come on right away. It lets you have a little power oversteer, but not too much. Porsche stability control is MUCH better than BMW ever was, but with the new system I think it getting much closer.

Anyone have similar experiences?

The point is that on the street you should not be creating that type of yaw change and slip angles in general in order to need the "extra" slip of mdm. You should be driving normally on the street and thus the ONLY time you will have the traction control engage is in an emergent unexpected situation, in which that case you will want the system to implement as quickly and fully as possible.

If you are playing boy racer on the road than sure it is better than not having anything but the point is you should not be needing any extra slip angles on the road-you should be driving like an adult

[rye m3]

Originally Posted by Ateam

The point is that on the street you should not be creating that type of yaw change and slip angles in general in order to need the "extra" slip of mdm. You should be driving normally on the street and thus the ONLY time you will have the traction control engage is in an emergent unexpected situation, in which that case you will want the system to implement as quickly and fully as possible.

If you are playing boy racer on the road than sure it is better than not having anything but the point is you should not be needing any extra slip angles on the road-you should be driving like an adult

I knew I could count on you.

I was so tired of the older traction control that would literally bog the car if you made a quick take off and sharp turn. The MDM allows just a bit of wheelspin without bogging the car down with the traction control. If you know your car and how to drive it, this is hardly a dangerous situation. This has nothing to do with slip angles.

[gblansten]

Originally Posted by rye m3

I knew I could count on you.

I was so tired of the older traction control that would literally bog the car if you made a quick take off and sharp turn. The MDM allows just a bit of wheelspin without bogging the car down with the traction control. If you know your car and how to drive it, this is hardly a dangerous situation. This has nothing to do with slip angles.

My experience is aligned with yours on this issue.

[SD-E93-11]

Originally Posted by rye m3

I've seen several posts suggesting driving with MDM active on the street was akin to inviting a crash. I've driven with it on in low traction situations, such as heavy rain and find the intervention very close to the traction control on a 997. It comes on, but doesn't come on right away. It lets you have a little power oversteer, but not too much. Porsche stability control is MUCH better than BMW ever was, but with the new system I think it getting much closer.

Anyone have similar experiences?

Not flaming you, but I'm not understanding a couple of your points. MDM is a mode of DSC, and DSC is the equivalent to Porsche PSM so I'm not sure what you're comparing here, DSC vs. PSM or MDM vs. PSM off?

I had a 997S Cab and as I recollect PSM could be turned off, but was never really 'off' as it was automatically reactivated under certain conditions. I don't know what makes you say PSM is better than DSC, but I'm not sure if that's an apt comparison as imo PSM is principally concerned with making sure your rear-engined rocket is not pointed backward down the street so it's doing a harder job that providing stability management on a front-engined rwd. I guess that makes it 'better'. But then I'd have to say that driving in MDM is safer for the street than driving a 997 with PSM off which from my experience would be extremely ballsy (read as 'stupid').

However, when considering systems to dial in driving dynamics, my opinion would be that EDC + DSC in the m3 works better than PASM + PSM in the 911, YMMV .

[rye m3]

Very good clarification. I am referring to MDM engaged, i.e. the newly refined, less intervening mode of traction control in the DSC. On Porsche the PSM engaged as well. A comparison of the MDM mode on, with standard traction control on other cars. I found the PSM would let you get sideways and intervened in a way that saves you, but it does assume you know what you're doing. So, separate and only view the DSC and PSM systems.

Only problem I have with MDM is that I can't just leave it on. Only engaging it with the M button is a pain, since it isn't on when you start the car and I prefer to have the "full sport" settings tied to the M button.

I'll agree, I believe, that I like the BMW EDC much better than the Porsche PASM. The Porsche system was stupid, off was too soft and on was way too stiff. BMW comfort is great for rough roads or with passengers. Normal is a great balance and Sport is stiff, but not jarringly so.

[Ateam]

Well why ask then? Have at it and use MDM like a boy racer

[luis_m3]

Originally Posted by Ateam

Well why ask then? Have at it and use MDM like a boy racer

What's with you and boy racers?

[///M Rakete]

Originally Posted by rye m3

I've seen several posts suggesting driving with MDM active on the street was akin to inviting a crash. I've driven with it on in low traction situations, such as heavy rain and find the intervention very close to the traction control on a 997. It comes on, but doesn't come on right away. It lets you have a little power oversteer, but not too much. Porsche stability control is MUCH better than BMW ever was, but with the new system I think it getting much closer.

Anyone have similar experiences?

Turning DSC off on the street is certainly questionable but I don't think running with MDM is.

[K-M3]

Originally Posted by luis_m3

What's with you and boy racers?

he doesn't like them!!!! lol!!!! just taking a quiet jibe at you A-team.......

[SROC3]

Originally Posted by Ateam

The point is that on the street you should not be creating that type of yaw change and slip angles in general in order to need the "extra" slip of mdm. You should be driving normally on the street and thus the ONLY time you will have the traction control engage is in an emergent unexpected situation, in which that case you will want the system to implement as quickly and fully as possible.

If you are playing boy racer on the road than sure it is better than not having anything but the point is you should not be needing any extra slip angles on the road-you should be driving like an adult

agreed. you should not have MDM on during any street driving condition. its borderline crazy to do that. even if you are a professional driver. I've seen too many accidents in P-cars, Evos and M's. All because they think they are street racer cool.

Do the general public a favor and keep it on Full DSC people.

[SenorFunkyPants]

There is no "one size fits all" rule to using MDM or even no DSC at all. If you are a good enough driver then you should know what level of traction control you can use and remain safe.
If you don't know then you are out of your depth in an M3.
I use MDM in the dry and when the temps are above ~10C as if nothing else you lose (WOT low gear) performance if the system detects the slightest loss of traction with full DSC on....plus some of the power slides you can provoke when using MDM are brilliant

[DivideBYZero]

So many Hallmark channel "OH MY GOD, THE BABY!" posts in here...

[rye m3]

Originally Posted by SenorFunkyPants

There is no "one size fits all" rule to using MDM or even no DSC at all. If you are a good enough driver then you should know what level of traction control you can use and remain safe.
If you don't know then you are out of your depth in an M3.
I use MDM in the dry and when the temps are above ~10C as if nothing else you lose (WOT low gear) performance if the system detects the slightest loss of traction with full DSC on....plus some of the power slides you can provoke when using MDM are brilliant

Agreed. At least someone else knows what's going on.

Slip angle has to do with the relative lateral acceleration, i.e. an 18" tire allows a greater slip angle than a 19" therefore you have more warning before the tires breaks loose. I hope some owners here are riding on 18's, because you will certainly be blind sided when 19's go away.

I'm happy with the MDM, just wanted to see how others related experience. If you think MDM is only for the track, please don't buy a 997 because the traction control is about the same. I guess you will end up in a curb somewhere...

[Mr. ///M3 RD]

Originally Posted by Ateam

If you are playing boy racer on the road than sure it is better than not having anything but the point is you should not be needing any extra slip angles on the road-you should be driving like an adult

[mkoesel]

Originally Posted by rye m3

I've seen several posts suggesting driving with MDM active on the street was akin to inviting a crash.

Really? How many is several? Because I'll bet there are several hundred - maybe even several thousand - over the life of the forum that would say the exact opposite.

Ignore the fringe minority and do what makes sense.

[smmmurf]

Originally Posted by rye m3

I'm happy with the MDM, just wanted to see how others related experience. If you think MDM is only for the track, please don't buy a 997 because the traction control is about the same. I guess you will end up in a curb somewhere...

+1

Originally Posted by SenorFunkyPants

There is no "one size fits all" rule to using MDM or even no DSC at all. If you are a good enough driver then you should know what level of traction control you can use and remain safe.
If you don't know then you are out of your depth in an M3.
I use MDM in the dry and when the temps are above ~10C as if nothing else you lose (WOT low gear) performance if the system detects the slightest loss of traction with full DSC on....plus some of the power slides you can provoke when using MDM are brilliant

+2

Originally Posted by mkoesel

Really? How many is several? Because I'll bet there are several hundred - maybe even several thousand - over the life of the forum that would say the exact opposite.

Ignore the fringe minority and do what makes sense.

+3

[elh0102]

These threads about DCT amuse me. I agree, for an experienced driver, the M3 is about the easiest car to control as anything I have ever driven. It’s well balanced, has a sufficient amount of protective understeer, modest power and meager low-end torque, all of which result in a very forgiving car in which to learn or improve handling dynamics. But I’m not sure why that should induce some folks to routinely drive without DCT on the street. My car does not have MDM, since I feel like I want it either on or off. The only car I have owned that had a more aggressive traction/stability control mode that I felt was useful, was the ZO6 Corvette.

Seems like whether on track or street, the simple test is whether or not DCT is routinely intervening. If it is, then there is something to firgure out. The driver could be grossly exceeding the car’s handling limits, in which case more learning is indicated. Or, the driver is bumping DCT in situations in which he/she would remain in control without it, and maybe be faster (or maybe not). But, except for the occasional childish fun in an empty parking lot, the only reason to turn off DCT is to achieve faster cornering capability. Since we are talking about maybe the top 5% of the car and driver’s potential, turning it off for general street use doesn’t seem to me to make a lot of sense. It’s not a matter of competence really. I drove a 996 GT3 a lot of miles on track and street, a car with no electronic gadgets, and I never has a problem. But, had I hit the unexpected patch of sand or oil, and the application of braking on one corner was needed, stability control would have been appreciated. Being able to handle the car without it misses the point, I think. I don’t anticipate driving into a crash, but I’m not cancelling my collision insurance.

[SD-E93-11]

^^

...boy, you guys just can't wait to turn every thread into an argument about DCT