I Want to Build a Go Fast RC !

[zeropointbug]

I say that because there are racing wings for the rear of the car, but underneath the bumper, that points down towards the front of the car, creates a low pressure and thus downforce on the car.

I would at least put a full lexan under body as to create a consistent air flow over the car, top and bottom. IMO.

[PBO]

Originally Posted by zeropointbug

I say that because there are racing wings for the rear of the car, but underneath the bumper, that points down towards the front of the car, creates a low pressure and thus downforce on the car.

I'm not sure what you're explaining?

As for the enclosed underside, it has been done & Nic Case makes the best example with one of his streamliners



If you look at the large image you can see channels that train the underbody airflow out of the vehicle which does create low pressure

Sunny mentioned leaving openings for airflow to enter the inside of the vehicle - this also works and both Nic & Sunny are using the venturi effect. If you don't create a venturi (somewhere for the air to escape) you are typically creating an aerofoil (the top of the body resembles the top of a wing, the flat, solid bottom - the bottom of the wing) which in itself creates lift because the airflow over the top is at a lower pressure than the airflow under the body...then you suffer blow overs at a certain speed depending on length/width/weight/speed

So it can be done but without the veturi effect the airflow underneath compresses to become higher pressure than the airflow over the top...you can of course change the airflow over the top by changing the body shape to create lower pressure than underneath but it's much harder than creating venturi's

I hope that makes sense? I've glossed over a few things