[JohnAh]

I´m trying hard to sober up and not start a heavy modification before i have the car running in standard shape. -It´s hard though...
When the car is street-ready I can make a cardboard prototype for the Kamm-back and meassure the difference in fuel consumption. I have a similar "longnose" V4 for family car but I don´t want to lower it´s "WAF" by strange mods. It´s better to wait until I have my personal experiment vehicle.

But a sober thinking doesn´t stop me from dreaming:

This looks really nice! The sloping back is 15 degrees and the final area is a lot less than 50% of the maximum projected area. One problem with this design is where (and if) to put the rear window(s). My dogs won´t like the size of what´s needed to get a proper view on a sunny day, but they will definitely like the extra space!