This carburetor is perfect for racing classes where 2-barrel carburetors are required. It features a manual choke, center hung float bowl, universal throttle lever, all-metal parts, and replaceable jets. It also includes a power valve, high flow venturi, and a standard 5-1/8 air cleaner flange. According to Murphy, Rochester began producing its two-barrel carburetor in 1954. It went into mostly General Motors automobiles and trucks. The cfm (cubic feet per minute-a measure of how much air the carburetor can flow) on the Rochester 2G ranges from about 225 cfm in the smallest...