This event is for ages 13-18. A straight-line acceleration contest between two cars, usually starting at different times, from a standing start over a specified distance, usually a quarter-mile or an eighth-mile. Racers line up in front of a countdown device called a Christmas Tree. When they leave the starting line, timers record how long it takes them to reach the finish line. This is called elapsed time, or ET for short. Top speed is also recorded.