All racers must be powered by a Continental O-200 engine (the same 100 hp engine used in a Cessna 150 trainer). The weights and size of every major part must be within stock limits. The cam profile and carburetion are strictly controlled. The racers must have 66 square feet of wing, weigh at least 500 pounds empty, and have a fixed landing gear and fixed pitch propeller. These racers have evolved for 50 years and are the only thoroughbred racing airplanes in use today.
These rules were designed to provide a fast and economical racing class. They have succeeded well in both counts. IF1 Air Racing is one of the fastest sports in the world. These racers routinely post laps speed around a 3 mile oval in excess of 240 mph, and have been clocked on the straightaways at well over 270 mph, all while flying only 35 feet off the ground.
Fifty years ago, in 1947, the Cleveland Air Races marked the first year of IF1 racing. Since then, International Formula One has seen more pilots compete in more different airplanes, in more races and in more countries than all other classes of racing combined.