Bumper Lips

Aerodynamics, the study of the motion of air around an object, was first extensively used for the development of aircraft, but aerodynamic forces as they applied to automobiles were at first not completely understood. Reducing drag was obviously a good thing, but some early streamlined vehicles actually lifted and became unstable at speed. The air flowing under the car was soon recognized as part of the problem.

Air flowing under a car creates two problems for a ride at speed. The first problem is drag created by the irregular shapes of the mechanical components. To eliminate this drag many race cars have smooth undertrays. The second problem is lift created by excessive air flow that lightens the front of the car and reduces traction at the wheels, which can make the ride unresponsive and difficult to handle.

Reducing air flow under the vehicle can reduce drag and lift, but doing so also creates an additional benefit. Decreased air going under the car forces more air around the sides and over the top of the car. The limited amount of air that does go under the car travels at increased velocity, creating a low pressure area. The greater pressure above the car creates downforce that helps the car stay glued to the track, improving tire traction for propulsion and steering. Bumper lips, also called air dams and spoilers, are the aero mods used to reduce air flow under the vehicle.

Splitters work in conjunction with bumper lips to create downforce. They extend horizontally forward from the bottom of the lip. When a car travels at high speed, the blunt front end creates a high pressure zone in front of the car. The splitters divide this high pressure air from the high velocity air flowing under the car, creating downforce. Road race cars often have adjustable splitters to control the amount of downforce, in an effort to maintain an aerodynamic balance between downforce and drag. To be most effective, bumper lips and splitters should be used with side skirts and a diffuser.

Beyond all the techno-speak, bumper lips and splitters just make your car look better. They give your car the appearance of a racer and make it look like it’s been lowered, even if you haven’t modified your suspension, especially when used in conjunction with side skirts. We have bumper lips for most popular late model cars in a range of attractive shapes and styles, manufactured from durable materials including carbon fiber, ABS plastic, fiberglass, and urethane. All of our bumper lips are designed for the specific application, so you can be assured of easy fitment and an awesome appearance.