I was salvaging from the scrap bin at work and decided to aero it up while I was there. A small pallet is against the cab window, sawed on one end for the right height. Three sheets of ply form the base, one forms the angle. Attached flow all over the place! A final version would open like Bondo's, and hopefully weigh 100lbs less!
Note clearance at front corner of tire is about .5", but no rubbing has been noticed. I had to wad up a cardboard shim for the fender flare to get the clearance right. I think this is the right shape for trucks. Sort of inspired by motorsport blister fenders. My bedliner had a little gap along the rails that I shoved the cardboard up into, then taped the seam.
Hopefully I can get some photos of tuft testing in action. The ones on the wheel skirt line up starting at 15 mph. I taped out to the bumper to mitigate the parachute effect. The sides are mainly cardboard rectangles, scored and folded over the plywood. The air almost follows the red tape angle, but actually cuts a little sharper up onto the top. One tuft on the side did poke up above the fold, but we added some tufts just inboard from there and the flow seems to re-attach and turn to the rear. All tufts on the plywood point straight back. My WWU VRI buddy warned I might get a venturi curling off the trailing edge, but strings undearneath show calm air behind the tailgate.
Just black duct tape. Still trying to figure out how to do an air dam. First step is to get rid of the stock one, which I highly doubt has any function other than to limit my approach angle. Highway testing after the cap and skirts showed lower than normal coolant temps, and the grill block maybe brought it back up to normal. Still, most small Fords (mine included) overheat, so I plan to switch to an electric fan (which will also help FE) and duct the air up through a hood vent. Any final grill block would be quick release, just like the rest of it. The tape is covered in bugs after one drive, so I think I'm getting some brick effect. Future plans, then, would be a more angled nose.
So, although there may be better angles, I did pretty well for my first try. I'm open to ideas!
I need the bed soon, so a-b testing will occur soon. Then I'll get to see how bad mpg is with a lumber rack. Yuck.