Dragracing is a fun way to race your car and see what it can do. A drag race is an acceleration contest from a standing start between two vehicles over a measured distance, either a quarter-mile (1,320 feet) or an eighth-mile (660 feet).
A drag race is started by means of an electronic device commonly called a Christmas Tree because of its multicolored starting lights. On each side of the Tree there are nine lights: four small amber lights at the top of the tree, two for pre-stage and two for stage, followed in descending order by three larger amber bulbs, a green bulb, and a red bulb.
Two light beams cross the starting-line area and connect to trackside photocells, which are wired to the Christmas Tree and electronic timers. When the front tires of a vehicle break the first light beam, called the prestage beam, the pre-stage light on the Christmas Tree indicates that the racer is approximately seven inches from the starting line.
When the racer rolls forward into the stage beam, the front tires are positioned exactly on the starting line and the stage bulb is lit on the Tree, which indicates that the vehicle is ready to race. When both vehicles are fully staged, the starter will activate the Tree, and each driver will focus on the three large amber lights on his or her side of the Tree.
Depending on the type of racing, all three large amber lights will flash simultaneously, followed four-tenths of a second later by the green light (called a Pro Tree), or the three bulbs will flash consecutively five-tenths of a second apart, followed five-tenths later by the green light (called a Sportsman, or full, Tree).
Races are usually won or lost on the starting line. Here at SMOKEmUP.com we wrote a neat little reaction timer program to test your reaction time with a computer simulated chistmas tree. You can race the Full Tree or the Pro Tree.
Questions, comments, or suggestions about the reaction timer can be submitted on the message board here.