Thanks everyone for helping me understand the ideal shape better. I printed a picture of the car with the ideal teardrop slope then cut it out with scissors. To optimize the Kamm I simply stood to the side of the car closed one eye, then held the cutout at arm's length, lining it up so it eclipsed my view of the car. I then simply adjusted the Kamm's angle until it matched that of the cutout.
I'll take better pictures from more angles to better illustrate the Kamm construction but for the purpose of this thread these pictures should be helpful:
Below you can see the new Kamm, then the half teardrop overlaying the car lined up along the groundplane so that the highest roofpoint is the highest of the template. Looks pretty spot on
Check out my
fuel log for the latest tank which had the optimized kamm for only the last 100 miles or so. Set a personal best range record and FE record!