Published February 16, 2011
The move announced Wednesday is one of many NASCAR has made since last weekend's exhibition Budweiser Shootout saw speeds top 206 mph at one point.
The reduction of the restrictor plate is 1/64-inch and could cut about 10 horsepower from the engines.
Horsepower-sapping restrictor plates are used at Daytona and Talladega, the biggest and fastest tracks in NASCAR. The plates limit an engine's power by reducing the amount of air that flows into the carburetor.
The Daytona 500 is Sunday.