So basically for the last 1.5yr I've been making model of my Punto with game use in mind. It's got pretty accurate exterior so I thought I'd give it some aero modding.
This is what came as a result:
I thought I'd like a boattail but if I ever build it I want it to be easy to detach - I rarely go out of town so it would be just an extra load most of the time. I want it to consist of several parts so that it'd fit inside the car if needed. I also want it to be mounted on trunk lid edge and bumper edge. This, along with location of rear lights makes it hard to get proper smooth line of sides, but this should do the trick IMO. I'm not really sure about the blue part but there's no way to make it more narrow and still have it mounted on bumper front edges.
I imagine it'd be made of fiberglass with some tubes molded in on the edges to give it shape and help connecting parts. Yellow rails are there to prevent sides from collapsing. I'd also like to add a diffuser but I do not have underbody modeled yet.
Is this design of lower part going to help or hurt aero? Should I try and make a smooth transition between pink and blue parts? In virtual world everything is quick and easy to do so it's better to get it right there before actually starting IRL.
BTW - anyone could help me with CFD testing?