To continue on the track theme from yesterday, this question was sent in by MF reader Fred:

>When testing a car, driving autocross, or racing, do you leave the DSC engaged, turn it halfway off, or turn it completely off? People say that they want to be in control, not leave it to the computer. Does a competent driver really have better control in competition without the DSC assist?

That’s a great question Fred and one that I actually spent some time coming to grips with a few days ago. I spent quite a few laps doing back to back comparisons with DSC on and off at Putnam Park and I found the results potentially surprising. With DSC on I found that I carried no less speed out of corners. In fact I found that, as long as I kept my lines tidy exiting corners, the DSC was rarely even activated. And when it did come on it was for slight throttle retardation (essentially feathering the throttle) with speed and precision that would be impossible for a human. This precision was quite a surprise as compared with my experience with the R53’s system or even my BMW 3 Series. With the R53 specifically I found the DSC to be generally a little too liberal in terms of interfering with aggressive driving. It would seem BMW has honed the system on the R56 to the point that it’s not really a track day liability. Or at least not with an aggressive but relatively smooth driving style or at a flowing fast track like Putnam Park. Of course the answer could be different on tighter more technical tracks or with different driving styles (and certainly different when autocrossing).

Note: both car’s mentioned above we’re equipped with limited slip differential.