Help me design my partial Kammback

[AeroModder]

Originally Posted by MetroMPG

It also had "hard" shoulders (which I've since learned are to be avoided).

Why is that? My current kammback has hard edges, so what should I look for in the second design?

[COcyclist]

Sharp cutoffs at the rear are generally a good thing (short of a complete taper). A rounded body shape is better for good aerodynamics, think of the cylindrical fuselage of a passenger plane. Darin is referring to the bends or creases in the cardboard where it turns down on the sides of his hatchback. It would be somewhat better aerodynamically if those were more rounded. If the air pressure on the sides is not exactly the same at that coming over the top, rounded shoulders can allow those to equalize a little. Sharp shoulders can be vortex generators which increase turbulence and drag.

[AeroModder]

I see, thanks for the clarification.

[Weather Spotter]

ABA Testing update:

Kammback data:


Graph:


This seems to me to match pretty well with the coast down data from before.

[Weather Spotter]

More picts of car now that it is painted:

[aerohead]

It's 'seamless',looks like OEM from parts department! I don't know how onlookers wouldn't think it was just a 'factory' car.Realy nice!

[Weather Spotter]

Thanks for the complent!

up close you can tell that it is home made, but not without looking hard

[Varn]

I agree weatherspotter. You did a nice job of integrating your modifications. Sometime take a nice 3/4 view.

I hope I can do something like that for my camo minivan.