Restrictor plates are used in racecars as safety devices to slow cars down. The restrictor plate is a square aluminum plate that has four holes drilled into it. Hole size is determined by NASCAR and varies between 0.875 inches and 1 inch (2.2 to 2.5 cm). These plates are placed between the carburetor and the intake manifold to reduce the flow of air and fuel into the engine's combustion chamber, reducing horsepower and speed.
Technical advances of the past few years have resulted in the creation of racecars with the ability to climb speeds unthinkable twenty years ago. After a crash in 1987 in which Bobby Allison's racecar became airborne and almost reached the grandstand with hundreds of spectators, the quest was on to create a safer speed on the track. Beginning with the Daytona 500 in 1988 NASCAR mandated the use of resrtictor plates in an attempt to slow the cars down and improve safety.
This safety devise has both its supporters and its foes.
Supporters of the restrictor plates believe:
* The cars are more stable allowing the drivers to put on a great side by side race
* The slower speed will prevent out of control air-borne accidents
* Drivers will concentrate more on the strategy of the race and not depend solely on speed
Foes of the restrictor plates believe:
* This device prevents the drivers from actually racing the car
* By keeping the cars at a restricted speed and bunching the cars together, more multi car accidents will occur.
Whether a supporter or a foe of restrictor plates at this time it appears they are here to stay.