Bodywork Glossary
Aerodynamic: The ease with which air can flow over the vehicle during higher speed operation. An aerodynamically sound vehicle has very little wind resistance.
Aerodynamic drag: The resistance of air against an object, such as an automobile, trying to pass through it. Also referred to as air drag and air resistance.
Aerodynamic force: A force created aerodynamically, such as by an air foil.
Aerodynamic resistance: Resistance of the air against an object, such as a vehicle, trying to pass through it. The result of four factors; coefficient of drag, frontal area, vehicle speed, and air density. Also referred to as air drag, air resistance, and aerodynamic drag.
Air dam:
- A panel across a race car's front end, designed to reduce the air pressure beneath the vehicle for a better ground effect.
- Panels around the radiator to ensure that all air passes through, not around, the radiator.
Air duct(s): Tubes, channels, or other tubular structures used to carry air to a specific location.
Bonnet: British term for a vehicle hood.
Carbon fiber: A very strong, lightweight, synthetic fiber often used in race cars, such as Formula One and Indy cars, because of its lightweight and high strength.
Coefficient of drag (Cx): A measure of the air resistance of a moving vehicle; a measure of how much air is moved as the vehicle moves from one point to another.
Composite materials: The bonding of different materials, usually for strength, such as carbon fiber and fiberglass.
Downforce: The downward force of air on a speeding vehicle.
Draft: To follow another vehicle close enough to take advantage of the slipstream or partial vacuum created behind it at very high speeds.
Drag: The resistance of air against an object trying to pass through it.
Drag coefficient: A term used for coefficient of drag.
Dzus fastener: A screw-like fastener that may be removed or installed with a quarter turn, ideal for race-car body panels that may have to be replaced quickly.
Fiberglas: The trade name for Owens Corning fiberglass-reinforced plastic.
Fiberglass:
- The generic spelling of Fiberglas.
- A product used to fabricate or mold durable lightweight parts and auto body panels.
Firewall: The partition between the engine and passenger compartment.
Forward rake: A car having a lower front than rear, to create an extra down force at high speeds.
Frame: The substructure of a vehicle supported by the suspension system that supports the bodywork, engine, and power train.
Frontal area: The area, in square feet, of the vehicle's cross section, as viewed from the front.
Front clip: The complete replacement of the front bodywork back to the cowl or A-pillar.
Monocoque: A unitized, autobody-frame structure [with stressed-sheet-metal body panels].
Pop rivet: A fastener used to hold two pieces together.
Resin: The molten plastic part of fiberglass-reinforced plastic.
Resistance: An opposition to movement, such as wind against a vehicle.
Rocker panel: The sheet metal along the bottom of an auto body, beneath the doors, and between the front- and rear-wheel openings.
Roll bar: A tubular bar behind the cockpit of a race car to protect the driver in case of a rollover.
Roll cage: A tubular, cage-like structure surrounding the cockpit of a race car to protect the driver in the case of a rollover and to add strength to the overall structure of the vehicle.
Side marker light: Lamps installed in all vehicles sold in the United States since 1969 that permit the vehicle to be seen when entering a roadway from the side and to provide a means for other drivers to determine vehicle length (clearance).
Slip stream: A partial vacuum that is created behind a vehicle traveling at a high speed.
Spoiler:
- An aerodynamic device that spoils the airflow over the vehicle.
- A device attached below the front bumper to reduce drag by deflecting air away from the vehicle.
- A device mounted on the rear deck to provide a downward force.
Streamlining: The shaping of a vehicle body so as to minimize air resistance.
Subframe: A partial front or rear chassis frame often used in unibody design to support engine or suspension assemblies.
Undercarriage: The chassis of a vehicle.
