This thread inspired me to dredge up another concept, I see these were only tested on the sides, and would like to have an understanding of why rounded sides are everywhere when perhaps a sharp transition would be better. If the sides should be sharp for best aero (once the efficiency/handling compromises are understood) then that would seem a less complicated mod or one more likely to give results. A clear strip of plexiglass glued to the rear sides might suffice. Mini-boattail
But we don't know for sure if these specially designed VG would help on the top, the author speculates there.
http://ecomodder.com/forum/showthrea...-te-18133.html