[basjoos]

There are two approaches to handling air flow under the car for minimum drag.

One is to lower the car and adding an air dam to divert air around the sides of the car and side skirts to maintain the low pressure zone under the car. This reduces frontal area (lowers drag) and creates a low pressure zone under the car (increases downforce and also drag, since it takes energy to create the low pressure zone). This is the approach that most race cars use since it increases downforce. Many ecomodders also do this since it is easy to implement.

The other approach is to reshape the nose to lower the stagnation point at the front of the car to divert most of the air over and around the sides of the car. This is combined with smooth underpanelling and rear diffuser to provide a smooth straight path for the remaining air flowing under the car, and a mix of wheel spats, double side skirts, and wheel boattails to deflect air smoothly around the car's wheels (4 individual wheel fairings or 2-wheel pontoons on each side of the car). This approach has no effect on frontal area and, depending on how it is implemented, can increase or decrease downforce. This is the approach that most solar race cars use. When using this approach you need to exhaust your radiator air out of the front wheel wells or out the top of the hood to keep it from disturbing the smooth airflow under the car.