ASC+T and the track -- and JimC?

[Brian M Kennedy <kennedy@xxxxxx>]

Is it possible to turn off ASC but leave on the +T???

Why do I ask?  Well...

In a brochure, it says:
	All Season Traction utilizes the anti-lock braking
	system to reduce wheelspin and loss of traction on
	wet, icy, or oil-slicked roads, while limited slip
	differential helps transfer up to 25% of the power
	from the slipping drive wheel to the wheel with 
	better traction.

Another adds:
	Since the left and right wheels can be braked 
	independently, ASC+T is comparable to one of these
	devices with a locking action of almost 100 percent.

For track driving, this seems real good.  In a power oversteer
situation, it is often the inside rear wheel that will start to 
spin first (since it is unweighted -- even airborne sometimes).
And when it does, you'll lose 30% of your traction, not only
in the forward direction, but also lateral.  That loss can
then initiate oversteer.

As the driver, you need to reduce power gently to stop the
tire from spinning.  But the traction control system can do
something the driver can't:  it can apply brakes to _one_ wheel.
Effectively, the traction control system could allow you to 
apply more power through a turn by scrubbing off some of the
power to the inside wheel, and effectively transfer that 
power through the LSD to the weighted outside wheel.  Marvelous!


Unfortunately, there's the ASC part of ASC+T.  Quoting:
	ASC+T reduces engine torque as soon as a wheel 
	tends to spin, for instance on sheet ice. If this 
	action is not sufficient to restore tyre 
	grip, the T function (traction control) 
	takes over and the wheel brake is applied, 
	provided that road speed is not above 
	100 km/h (62 mile/h). Torque is reduced by 
	the engine's own management system.

Ack!  This seems far less desirable.  I'd rather keep control of the throttle
myself, thank you very much.  And I'd certainly prefer it to try the braking
approach first, and only after that fails or both wheels start spinning would I want
throttle cut-off.

However, then I find this quote:
	The ASC + T system intervenes in two stages:  When it 
	detects one rear wheel near the threshold of adhesion,
	it starts to rapid pulse the brake to that wheel (just
	like ABS).  When the second rear wheel nears the limit
	of adhesion, engine power is reduced.

	The first stage (single wheel braking) actually improves
	vehicle performance.  The second stage (engine reduction)
 	doesn't improve performance available, but it adjusts
	output so that all that is available is fully utilized.

That sounds more like it!  That's exactly what I'd want.  And 
then even better, that quote goes on to say:
	The dashboard ASC + T light only flashes when the system
	enters the second stage, and is reducing engine power.
	It doesn't flash when the system is only braking a wheel
	about to slip.  This can be demonstrated most easily in
	the snow.  By using the dashboard button to turn ASC + T
	on and off,  it becomes immediately apparent that it is
 	assisting traction even when the light doesn't come on.

Wow!  That sounds like the button just turns off the ASC and 
leaves the traction control working.  Is that so???


QUESTIONS:

* Is it possible to turn off ASC but leave on the traction control?
  
* Is that in fact what the existing ASC button does?  Or does the
  ASC button also turn off the traction control via braking?

* Is it true that the light only flickers on when the torque is being
  reduced, but NOT when the brakes are being applied?

* JimC software prevents cut-off at high speed and can delay cut-off
  at redline.  Could it also prevent cut-off by the ASC system?

* Does it already?  (One thing I noticed in my newly sharked car is
  that its a lot easier to accidentally spin my wheels a bit; kind of
  like when I turned off the ASC+T system before sharking.  Could be
  just the added power; OR, ideally IMO, it could be because 
  sharking also eliminates the cut-off by the ASC system.  
  Anyone know?  Jim?)

* Does anyone know of any good, complete documentation on ASC+T?
  The Users' Manual has less than the marketing materials.  And
  the marketing materials are, well, marketing!

* For those of you that drive at the track, do you turn off ASC+T?
  If so, why?  If not, why?  (Feel free to respond privately; I
  will summarize the results, assuming I hear any.)

Thanks in advance for any answers,

Brian
98 M3/4, Shark infested, Dinan suspended and braced, X braced, forged

------------------------------