[gumby79]

AutoSpeed - Blowing the Vortex, Part 4
VG as i understand them. Running backwards as the article suggest seems counter productive as in this format it takes 2 VG each at opposite15°to air flow to achieve a single pair of counter rotating vortices ... 2 pucks =1 pair of vortices . And causes an increase of non aerodynamic frontal area. May as well glue bricks to the car ,there cheaper.
Turn them 180° and now you have 1 puck and 1pair of counter rotating vortices , and a streemlined additional frontal area. Much less math and drawing pictures on your car to figure out the proper orientation. based on tuft testing to determinethe befor during and after points of separation at various speeds to align the skinny end with the Wind(forward) . My choice after researching points to using a type2 skinny end with the Wind. With the skinny end aligned with the tuft ,putting the 2 tailes at +&- 15° to the air flow.

Their example of VG it the belly pan the vG action is more a saw tooth air dam . Showing a positive impact on aerodynamic efficiency. A better result wou have beenfrom a full air dam.
Their only use of tuft tested VG was on thire only non instant mpg . Making the visible improvement un measurable.

The CRX looking hatchbacks looks like the VG is located at the point of reattachment disturbing this reattachment. With no place for the vortex to stableize (hence the 1/3 forward its gota land and stableize before it can help). It appears as though this car could have shown improvement it the VG had been applied in a similar positions as the Insight and determined with tuft testing.