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Old 01-17-2013, 08:39 AM
ChasR ChasR is offline
Officially Welcomed to the 'Fest
Location: Atlanta
Join Date: Aug 2012
Posts: 174
Mein Auto: 335d, E28 M5, Clubman S
It's been raining for days in Atlanta, so the Quaife has gotten a pretty good workout. It makes a dramatic difference in the way DSC behaves. It's obvious the DSC logic is written to accommodate a LSD (or TBD in the case of a Quaife). With the Quaife you can lacceletate rapidly, straight or turning, without DSC engine intervention kicking in until you spin the rears too fast or start to slide. It's much safer to drive as there isn't the virtual stall if you apply a little too much throttle.
The fact that the quaife works so well, and so much better than DSCs automatic brake differential (ABD) has led me to research what the DSC system logic really is. I haven't found it yet, but my seat of the pants take is that in DSC if one wheel spins the first step is to cut torque through engine intervention, if it continues to spin, DSC invokes ABD, If you turn on DTC, by pressing the button, this logic is reversed, ABD is invoked on one wheel spinning and if both wheels spin past the limit (which is higher than the DSC limit) engine intervention kicks in. DSC will allow some wheel spin as long as both wheels are spinning, which is where the Quaife come in, doubling traction and spinning both wheels if too much throttle is applied.

If you live in a snowy/icy climate and are concerned about the Quaife not working with one wheel on ice or off the ground, punch the DSC/DTC button and ABD will brake the spinning wheel and off you go.

Last edited by ChasR; 01-18-2013 at 04:27 AM.
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