You saw it here first, folks!
While perusing the photos of
BMW's new wind tunnel facility, I happened to notice the strakes on the top of a 3-series model being smoke tested on their rolling road:
Oooh!
OK, yes I'm being a bit facetious... people seem to latch on to VG's as a magic bullet, and they're not. Remember: when optimized by Mitsubishi, they estimated delta style VG's made a difference of -.006 to the drag coefficient of the Evolution sedan.
-006 is nothing to sneeze at, don't get me wrong. But it's not a magic bullet, and a change of that magnitude won't show up in either tank-to-tank or controlled-as-possible testing:
I think what's MUCH more significant from BMW's testing is the full set of
four fender skirts that automatically cover the 3-series wheel wells after it jettisons the wheels and enters flying mode:
