When a car is in motion, the air that flows underneath it causes a change in pressure between the top and bottom of the car generating a force called lift, which causes the car to rise slightly. Lift results in less surface area of the car’s tires being in contact with the ground, reducing traction and changing the handling of the vehicle. A moving vehicle also creates drag, which slows the speed of a vehicle, as air flows over, under and around it.
Ground effects, also known as body kits, are extensions attached to the lower part of an automobile’s body designed to counter the forces of lift and drag. Reducing lift and drag improves the handling and increases the speed of a vehicle. The improvement to a car’s handling is the reason that many racing cars have ground effects installed. Ground effects are not just for racing cars however and many vehicles on the road today have body kits installed.
A front spoiler, or front air dam, is located under the front bumper of a vehicle. The front spoiler reduces lift and drag by directing air toward the sides of a car and preventing air from flowing under the vehicle. Side skirts are installed on the rocker panels beneath the doors and direct the flow of air towards the rear and prevent air from flowing underneath the car. Rear skirts are located underneath the rear bumper and also prevent air from flowing underneath the car.
Ground effects can also enhance the overall appearance and aesthetics of a car. They reduce the distance between the ground and the bottom of the vehicle and create a lowered, sporty, more aggressive look. There are a wide variety of ground effects body kits to choose from and the driver can modify the appearance of his car in many different ways. While car body kits can be installed as a do it yourself project, many owners opt to have the body kits professionally installed.
Many car manufacturers also sell vehicles with ground effects as part of a premium, sports or performance trim package. The advantage of choosing a vehicle that has the body kit installed by the manufacturer is that the accessories would be covered under the manufacturer’s warranty. Ground effects installed as an after market item would not be covered under the vehicle’s warranty and in some instances may void the warranty.