|ACO: Automobile Club de l'Oest, the French sanctioning body for the 24 Hours of Le Mans whose rule book is the basis for the ALMS.
BIAS: The setup of brakes (usually adjustable by the driver) that changes the braking power from the front to the rear (and vice versa).
DAG: Acronym for “Data Acquisition Geek”, the computer expert who maintains the team’s data acquisition and analyzes the data.
DIFFUSER: The bodywork at the rear underside of the car that controls the exit of the underside airflow and provides downforce.
DOWNFORCE: The downward pressure on the car created as the car moves through the air at speed. The race engineer is always looking for the right balance of downforce vs. straight-line speed. The Dyson car produces enough downforce that at 135 mph, you could run the car upside down and it would stick.
HAT DANCE: The ritual of photos taken after a race on the podium, with the top three drivers changing sponsor hats for each photo.
FRONT SPLITTER: The car's front aerodynamic device that controls airflow. The air above the lip goes through the radiator and intercooler and the air below goes under the car.
G FORCE: The force exerted upon drivers as they accelerate (positive G’s), decelerate (negative G’s) and turn (lateral G’s). ALMS drivers often endure up to five “G’s”, in particular during cornering and on certain uphill/downhill sections of high-speed race tracks such as Road Atlanta and Road America. By comparison, the space shuttle leaves its launch pad at approximately four “G’s”.
GROOVE: The fastest "line" around the the circuit. Can change during the race as oil and tire rubber is thrown-off the cars.
KITTY LITTER: Used to describe two things: the absorbent powder that soaks up fluid spilled on the track (often real kitty litter) and the gravel runoff areas on the outside of road course turns that help slow cars that go off the track.
INTERCOOLER: A heat exchanger added to a turbocharged engine to cool the air as it leaves the turbo. Cooler air is denser and makes for more horsepower.
LOLLIPOP: The sign on a stick held in front of the car to guide the driver where exactly to stop in the pit and inform the driver to reset the fuel meter. Often shaped in the form of the sponsors product.
MARBLES: The off line part of the racetrack that becomes dirty and slippery from the rubber thrown off by the soft tires.
STICKERS: A new tire, with the manufacturer’s sticker still on the tread.
SLIP: An acronym for the electronic “Speed Limiter in Pit lane” device that keeps the car at the pit lane speed limit by holding a button on the steering wheel.
SWOL: An acronym referring to the electronic “Shift With Out Lift” programming that allows gear shifts without taking one’s foot off the accelerator.
TEAR-OFF STRIPS: Transparent plastic strips covering the driver’s visor that the driver tears off during the race as they become dirty.
TELEMETRY: The radioing of the cars performance data to the engineers in the pits. Used for both car set up and monitoring potential mechanical issues.