On this page about Restrictor plate:
A Restrictor plate or air restrictor is a device installed at the intake of an engine to limit its power. This kind of system is occasionally used in road vehicles (e.g., motorcycles) for insurance purposes, but mainly in automobile racing, to limit top speed and thus increase safety, to provide equal level of competition, and to lower costs.
Restrictor plates are devices used in NASCAR racing at the two longest superspeedways, Daytona and... the restrictor-plate rules were implemented in the 1980's. It certainly makes for a different style... often referred to by fans, drivers, and crew members alike as restrictor plate racing...
engine has no power-valve and produces around 22hp (age 13-16), and the Minimax has a restrictor plate in the carburettor which restricts it to about 18hp. There is also the RM1, which has two gears...
running there and at Daytona run with restrictor plates limiting the amount of air which could be... different than that at other superspeedways and to be referred to by NASCAR fans as " restrictor-plate...
the NASCAR race at "Indy" to be run without the use of carburetor restrictor plates like those used...
Talladega), restrictor plates must be added to carburetors to restrict airflow and, therefore... track where restrictor plates are not mandated. Unrestricted, NASCAR cars run at over 750 horsepower...
International Speedway; however, NASCAR mandates the use of restrictor plates on the carburetors of all cars...
speeds much lower than at other tracks of similar lengths; restrictor plates are not needed here. The...