[aerohead]

You're graphics are top-notch! I like where you're trying to go but my brain has hit two glitches.I suspect that from the driver position,unless the vanes are splayed out to respect line-of-sight through the rear view mirror,you'll develop tremendous blind-spots at each side of the rear windshield.---------- The other thing that may enter the picture,is much surface area friction and shedding vortices behind each vane due to dead spots close to and directly behind each vane.--------- Something that worked on my CRX,was to keep the end plates and blend them into the C-pillars,then,at the "top" of the vanes,construct a single flat spoiler shelf which runs horizontally right up to the backlite.The air captured below the shelf will be below the Kamm profile,and above it,you'll have a single attached vortex which the outer free stream will bounce off,reattaching at the tail of the shelf.--------------- There's a lot less skin friction,it's simpler to construct,rear visibility is maintained accept at the extreme sides and it's lighter and should do the cleanup just as well.