[brucepick]

COcyclist,

Thanks.

I'm also concerned about smoothness of the transition to the roof extension. Have shaved the leading edge of that panel to a knife edge hoping to keep attached flow, or at least not mess it up terribly. Duct tape to hold it down to the roof.

NO project is complete without duct tape!! Check out the dark green 3M "No Residue" type at Home Depot and other places. Holds great, no crud afterwards. Kinda pricey though.

The flat panel that appears as a line was pretty clever but coastdown testing showed only slight gains if any. Not sure if I put the test notes in here but...

I'm still going back and forth on this project.

Tonight worked on a roof extension panel that goes rear and down over part of the rear glass. At least for this weekend's Green Grand Prix, I hope to run it with just the roof extension and shortened side panels to match the extension length.

Found you can extend the roof line pretty far back, and down, before you intrude on the rear view. Use that info bit there! Also, use the defrost grid area as an indicator of what you NEED to see. That is, the top 8-10 inches of glass have no defrost wires. Your roof extension can block your view of that upper glass because you don't really need it. That's the theory I'm going on now, anyway.