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BDL
06-07-2008, 01:53 PM
The July 2008 edition of Road and Track discusses the latest developments in stability control. I have a '99 M3. How does it's version work and how effective is it? Thanks.

fun2drive
06-11-2008, 08:52 PM
You don't have stability control first of all if you are speaking of your M3. However if you are asking about how the stability control system work see below...

Other SC systems typically work on by measuring the the wheel angle (measured from having the wheels pointed straight ahead to the angle you have them turned at) and the actual yaw angle and comparing them. If the actual yaw angle is greater then the wheel angle then the car is skidding. If it is skidding the SC system will brake whatever is needed to bring the car under control. It will not usually allow the car to get away that far and you can exceed the limits of the system by being overly agressive. The engine will usually have the power reduced as well.

You might be thinking of ASC which is a traction control or All Season Control. It does reduce the power to the engine and will brake whatever wheel is losing traction. M3's have a % limited slip but it will break lose at times...

BDL
06-12-2008, 01:28 PM
Thanks. That clears it up for me.

Fantomas
06-26-2008, 02:21 AM
You don't have stability control first of all if you are speaking of your M3. However if you are asking about how the stability control system work see below...

Other SC systems typically work on by measuring the the wheel angle (measured from having the wheels pointed straight ahead to the angle you have them turned at) and the actual yaw angle and comparing them. If the actual yaw angle is greater then the wheel angle then the car is skidding. If it is skidding the SC system will brake whatever is needed to bring the car under control. It will not usually allow the car to get away that far and you can exceed the limits of the system by being overly agressive. The engine will usually have the power reduced as well.

You might be thinking of ASC which is a traction control or All Season Control. It does reduce the power to the engine and will brake whatever wheel is losing traction. M3's have a % limited slip but it will break lose at times...

While you are correct about what a stability control does, you got a few things wrong. ASC+T stands for Automatic Stability Control plus Traction. All M3's 96 and up have this, non-m3 models got the basic ASC (all season control). From my experience and you can test this in a parking lot, when cornering aggressively at low speeds the ASC tries to match the yaw angle to the steering angle during a slide, the light will blink. That part is nice, the T part sucks. If at any point your rear wheels are spinning faster than your front wheels there is a plate which sits in front of your throttle body slams shut, effectively lifting your right foot for you. This happens often on cold tires even when you aren't trying.

M3's also have what's called Hill Climb traction control, press and hold the ASC button for 10 seconds and you have limited the system to only use the rear brakes to control traction. I tried it out up a wet hill pulling out of a parking lot and I can still manage massive wheel spin between 75 and 100% throttle. Not sure if it keeps the stability control active

aavi
06-26-2008, 06:41 AM
that brings me to another question what are the 3 settings on the E36 M3, near the gear stick it has E, M and S...can anyone explain to me...

also when ASC light is ON that means everything like TC and all are OFF am i right? i have been confused by this please clear it up for me someone..

Bruce
06-26-2008, 07:10 AM
E, M and ahve to do with the atuo gearbox. Your owner's manual will explain this.

Yes, when the ASC light on the dash is on, the system is off. Again, this is covered in the owner's manual.

aavi
06-26-2008, 09:50 AM
E, M and ahve to do with the atuo gearbox. Your owner's manual will explain this.

Yes, when the ASC light on the dash is on, the system is off. Again, this is covered in the owner's manual.


i'am looking into a manual m3 now....they dont have these E, M and S modes right....i guess these are just for automatic driving when you need the ****s to be more sporty or something....not sure