sj3

Iceman: That was a great, clear explanation. However, if someone could provide a slightly different view. Basically, under what conditions/driver objectives should the driver touch the button lightly and under what conditions/driver objectives should the button be pressed and held? Also, does one get back to normal from either of these two states by just pressing the button again?

Thanks so much in advance,

Sam

Iceman

OK,

you press the button once, DSC partially off, DTC remains active
you press the button longer, DSC completely off, DTC also off

you press the button once after doing one of the above mentioned procedures, you return to full DSC.


DTC gives you more wheelspin. It controls only rear wheels.

One situation you don't want to use any DSC is track driving/racing, IF YOU KNOW WHAT YOU DO/HOW TO DRIVE AND IF YOU HAVE TOTAL CONTROL OF THE CAR. It allows drifting, in example.
One situation you want to use DTC is when you parked your car in/on snow. You go to DTC mode and the front wheels are not under the DSC control anymore and you can free your car and drive off.
You'd also like to use DTC only, when using max acceleration from a start. The wheels spin very short and it gives you max acceleration.

urbo73

I don't know about this one. If you're taking your E60 to the track, you've bought the wrong car IMO. I love my car, but it's not a race car. You can't throw it around like an M3, etc. This past weekend I played with DSC/DTC/"ME" on a very large icy/snowy parking area that was empty. It also had a "runway" leading into the area to get some speed going in. I even set up some cones to mess around. I basically beat the crap out of the car to see the limits of this sedan. Not that mine is that great compared to a 545 sport, but anyway I wanted to know its limits. I found that DSC fully on does a pretty damn good job, but it sometimes overcorrects or rather corrects 2x in an oversteer. I was faster through the cones with DSC off. I even enjoyed it more. With DSC on, I would be "fighting" at times with the car from natural instincts. With DTC, I didn't bother too much, since I couldn't really figure out what the hell it was doing. I would at times get wheelspin as much as I wanted and at others not. So that's why I posed the question here as to how does everything really work - or rather how IS everything supposed to work.

Your point about on the street is valid, DSC will have faster reaction times. But there are several things. One is I don't trust it 100% and know I may have to fight with it which scares me. And second, on the street/highway, in bad weather, I don't drive like a nutcase. The latter is most important. Because I've left DSC on (on purpose and because I've forgotten to turn it off) this past week, and I looked to see if anything was going on (looked for the light, felt, etc.) and I didn't feel much, except for when starting at times when it was preventing wheelspin. What that means is that in MY own driving, I'm not going to go 60mph, hit the brakes, and oversteer into a turn like a maniac. I take it E A S Y The only thing is avoiding other maniacs. But I just trust myself better if someone jumps in front of me, or if I have to hit the brakes, etc. But again, in this weather, DSC or not, it's best to just go slow and relax. Then you won't need to worry about accidents. Most people get into accidents because they can't drive in bad weather or ignore it and drive like they do in the dry. Oversteer just "doesn't happen" if you know what I mean. I've driven so many RWD cars with much more HP w/o any of these aids, perhaps that's why I look at it differently. For people like my wife, I of course don't tell her to turn off DSC! Karting and autocrossing help a lot, but that's not street. But it helps too. So does driving for many years in bad weather without electronic gizmos and common sense.

Iceman

urbo73,
first of all, you say "If you're taking your E60 to the track, you've bought the wrong car IMO", but YOU took a 530 to the track...
I find this very funny to read.
I can not understand the problem here!
What you say is nothing different than what I said!
But there is one thing I HAVE to disagree. You trust yourself better, but accept that the DSC reacts faster. So WHY do you turn the DSC off?
Do you think M. Schuhmacher would turn it off? I don't think so.

Of course oversteer doesn't happen, but that's exactly why there is DSC, because ppl make the cars oversteer, due to wrong driving/reactions. You seem to be very well trained, but you can not guarantee it either, that you will not oversteer, because nobody is perfect and you can fail... That's why you shouldn't touch the button in "normal" driving on the street.
But again... What you said is basically not different to what I said.
And if you want to turn it off, fine, do it - but it's safer when it's on!

urbo73

Iceman,

When did I say I took it to the track? I took it to test the DSC/DTC stuf in HUGE empty, icy parking lot with a long "runway" that let me get up to 45-50mph before getting into the lot. I don't plan to take the car to a track or back to that lot again. It was to test it. I would test a Honda the same way.. Neither are race cars. Try drifting with the E60 and you'll laugh! Try tossing out the back going into a corner. Not the car for that. Feels like a fat guy running the 100 meter dash.

I told you why I would and do turn it off. Because it doesn't work that perfectly. I found it sometimes 2x corrected or even 3x corrected a simple move that I had no problem doing myself in one move. It would cause the car to "stutter" sort of - brake weird. It just wasn't smooth and it interfered with my instincts. I couldn't just "let it go". And it would brake seemingly at the wrong time, etc. Like I said, I was faster through my 10 cones w/o it, so there! I trust myself bettter. And with it off, I don't need to worry about turning it off when I want wheelspin to go up a hill or dig myself out of snow, etc. The car is always the same, since I drive it the same.

Of course I agree that people make cars oversteer, and I'm not trying to even make any recommendation. Everyone can do what he/she wants. For most people it's probably better to leave it on. I don't disagree. I just disagreed about the racetrack statement. It's up to the individual - hence the option to turn it off or on.

I'm not sure how we got into this. My question was simply a techincal one as to how these systems are supposed to work, since deciphering the BMW literature is hard

It was not a question about IF I should have it on or off, etc.

Regarding Schumacher, he'd probably leave it on. Didn't he use such gizmos at Benneton? I'm more a Montoya fan - naturaly ability and less robotics

Iceman's worst nightmare: A guy with DSC off and with his foglights on

alohalc

...when it's not foggy .

jochet

OK,

you press the button once, DSC partially off, DTC remains active
you press the button longer, DSC completely off, DTC also off

you press the button once after doing one of the above mentioned procedures, you return to full DSC.


DTC gives you more wheelspin. It controls only rear wheels.

One situation you don't want to use any DSC is track driving/racing, IF YOU KNOW WHAT YOU DO/HOW TO DRIVE AND IF YOU HAVE TOTAL CONTROL OF THE CAR. It allows drifting, in example.
One situation you want to use DTC is when you parked your car in/on snow. You go to DTC mode and the front wheels are not under the DSC control anymore and you can free your car and drive off.
You'd also like to use DTC only, when using max acceleration from a start. The wheels spin very short and it gives you max acceleration.
[/quote]

Iceman, you my friend are a plethora of information, great post.

Guest

Just to add to the discussion:

Driving on heavy snow all weekend I figured the best way was
to turn DTC OFF(i.e. restrict it) and sometimes DSC OFF as well when starting to move. As soon as you get going turn in back on.

Sometimes in order to get going at all you need to turn DSC OFF completely, the wheels spin freely but at least you get out of the snow eventually!!!

urbo73

After all of this I still don't understand one thing - my main question to begin with!

Basically from what I read, "DTC only" allows wheelspin + DBC braking of the rear wheels (i.e. limited DSC in the rear). My question all along has been basically this:

What does "DTC only" buy me over "DSC off" in this case? I either want wheelspin or not! What is this quasi wheelspin with limited DSC (braking) on the rear wheels? Seems like a lot of hodepodge to me. And it sure felt like it when I tested it.

Stranger

I would say average drivers will appreciate the partial traction on the rear wheels when the situation calls for some wheel spin. If all 4 wheels spin in the snow or mud does it help to get the car going? I don't know.

Well, for advance drivers like you, perhaps you just leave it on or completely turn it off; just skip the DTC stage. No biggie.