I excel at the enthusiasm, innovation, and construction of mods but struggle a bit on the science and mathematics end of things. I'm hoping some of the more math/science gifted aero guys can help me get on the right track to optimize my
kammback and get the best results possible.
A few people have said it looks too steep and that to find the optimum shape, I needed to use only the top half of the teardrop image and line the bottom edge with the groundplane. Doing this does indicate that my angle is too steep. I planned on remaking the sides anyway to extend them beyond the frame so I'm thinking when I do this, I will also take the opportunity to round the corners and raise the angle. Before I do anything though I want to make sure I understand things right and that my thoughts toward a full boat tail are also on the right track.
Here is a 3 part picture that illustrates well what I am thinking. Here is a very short explanation of the picture:
- The top half of the teardrop (A) with the bottom edge along the groundplane and the highest part of the drop the highest edge of the roof. (I believe this is where I want the kammback to line up)
- I added a bottom half teardrop (B) with the top edge PARALLEL to the groundplane and the tallest point lining up with the rear skirt/bellypan edge. My thinking here is that a future boat-tail extention would follow the darker part where A and B overlap.
- Here I added a third layer, this time of the entire teardrop (C) sized so the tallest point spans the difference between the top (roof) and bottom (bellypan) of the car. It looks slightly steeper than picture 2.
It looks like I know where to raise my kammback to, which boat tail is best (2 or 3?)
Also, as for narrowing the width of the kammback and boat tail: if I took an arial photo of the car would i simply taper of following the full teardrop such that it's tallest point spans the entire width of the car?