You know, the more I look at my own design, I am wondering if I am driving it the right way. The tapered long angle was supposed to be the front, but it almost looks like it should be going the other way.
Ahhh, I was seeing the blunt end as the front as it would be more aerodynamic that way. But it is also more wing like in that direction and more likely to cause lift.
Add an airdam under the front end and skirts down the sides so that it prevents air rushing underneath. The much reduced airflow under the wing, erm, body will cause a lower pressure underneath sucking it downwards to counter the lifting from the faster airflow over the top. Also a hollow section under the floor will also drop the pressure underneath too.
There is a lot to take into account with car body design. It may be worth your while making a mini wind tunnel to test models with.
Here is a small scale wind tunnel.
I would advise fitting a bundle of straws into the inlet to make the flow more linear as it is drawn through the tunnel.
