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Discussion Starter · #1 ·
Ok raced a Mustang last night.. Beat him down..
But generated some questions about the DSC.

Im hoping the DSC was the culprit and not something else..

symptoms.

Was WOT out of 1st gear..
Clutched, let off gas, into 2nd and WOT...

BUT.

As I snatched into 2nd with clutch out.. the CAR BOGGED momentarily.
that took all the momentum out the vehicle.. Like it
hit a FUEL CUT or something. Was not the REV limiter.
Then it reved up normally.. I assume going into 2nd on a WOT
run, would make the rear end a little squirlly. but it didnt.

I SUSPECT, its the DSC at work.. BUT Im totally not certain.
So im asking this to ease my worries.

which leads to my 2nd question..

WHen doing WOT runs with DSC on.. Can it cause Detonation??
What does the DSC use to keep traction?? Does it retard the timing?
cut fuel?? or apply braking???? any insight will be great..

Thanks :thumbsup:

BTW: is there a way to make the DSC default OFF??
 

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Sounds like you activated DSC when you shifted. If you have a good clutch, that shift should break the back tires loose for a second, and DSC wont allow it. As a result, the car bogs. Normal operation of DSC.
DSC works by pulling the timing back and applying brakes as you thought. I highly doubt it would cause detonation, unless maybe you're running 80 octane from the 1930's. :D The DME on the S62 just wont allow it to happen.
Default off? Hmm...I seem to recall someone making a chip that made the car start up with DSC off and sport on, but dont hold me to that. IIRC I saw that years ago.
:cheers:
 

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Definitely your DSC came into action! I never race with DSC on, it kills my power in 1st, 2nd and even 3rd gear!!!!
 

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E39 MFIVE said:
Ok raced a Mustang last night.. Beat him down..
But generated some questions about the DSC.

Im hoping the DSC was the culprit and not something else..

symptoms.

Was WOT out of 1st gear..
Clutched, let off gas, into 2nd and WOT...

BUT.

As I snatched into 2nd with clutch out.. the CAR BOGGED momentarily.
that took all the momentum out the vehicle.. Like it
hit a FUEL CUT or something. Was not the REV limiter.
Then it reved up normally.. I assume going into 2nd on a WOT
run, would make the rear end a little squirlly. but it didnt.

I SUSPECT, its the DSC at work.. BUT Im totally not certain.
So im asking this to ease my worries.

which leads to my 2nd question..

WHen doing WOT runs with DSC on.. Can it cause Detonation??
What does the DSC use to keep traction?? Does it retard the timing?
cut fuel?? or apply braking???? any insight will be great..

Thanks :thumbsup:

BTW: is there a way to make the DSC default OFF??
There are some posts indicating that the rev counter may be a little slow to catch up to actual revs. So you may not see 7100 but you may have hit the limiter. If DSC intervenes, the symbol will flash on the insturment cluster.


Regards,
Jerry
 

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E39 MFIVE said:
Ok raced a Mustang last night.. Beat him down..
But generated some questions about the DSC.

Im hoping the DSC was the culprit and not something else..

symptoms.

Was WOT out of 1st gear..
Clutched, let off gas, into 2nd and WOT...

BUT.

As I snatched into 2nd with clutch out.. the CAR BOGGED momentarily.
that took all the momentum out the vehicle.. Like it
hit a FUEL CUT or something. Was not the REV limiter.
Then it reved up normally.. I assume going into 2nd on a WOT
run, would make the rear end a little squirlly. but it didnt.

I SUSPECT, its the DSC at work.. BUT Im totally not certain.
So im asking this to ease my worries.

which leads to my 2nd question..

WHen doing WOT runs with DSC on.. Can it cause Detonation??
What does the DSC use to keep traction?? Does it retard the timing?
cut fuel?? or apply braking???? any insight will be great..

Thanks :thumbsup:

BTW: is there a way to make the DSC default OFF??
All good answers to your question about your situation. The one that I cant subscribe to is that you were "hitting the rev limiter". As I saw in your post, you said you got the BOG as you let the clutch out and went WOT in second. This would mean you were at the lower end of the rev curve in second, as you had just gotten into that gear. This is no where near the limiter. BUT, You do need to watch the revs because Jerry is correct, you will actualy hit the limiter BEFORE the needle shows you have hit redline.

SO, what you had was a DSC MOMENT:D Kinda sucks to have that when your racing. Can leave you looking bad if your up against something stout:sad2:

Also Ard is correct I would be willing to bet that your indicator between your Tach and Speedo was flashing when you dropped the throttle in second. It will flash when the system is activated. It is an Amber colored circle with a triange inside it and a ! inside the triangle.

DSC's first response is to retard the ignition. Thats why the big hesitation. It will gradually give you the throttle back as IT deems acceptable without inducing wheel spin. If you were cornering it will also use the brakes to rotate the car to where you are telling it to go.
 
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