Abstract: Disclosed is an adjustable apparatus for regulating the flow of fuel into a carburetor by use of a specially designed fuel metering rod. The hollow rod includes four different sets of holes along its sides at one end, each set separated from the adjacent sets by ninety degrees (90.degree.). The holes of each set are graduated from large to small, and each set covers a different range of hole sizes. The rod slides into a housing on the side of the carburetor, the holes regulating the amount of filtered fuel delivered to the carburetor. By sliding the rod, different sized holes on the rod line up with the exit opening in the housing to the carburetor. Sliding the rod also moves a linkage which causes the opening or closing of the air valves of the carburetor. The rod may be removed and rotated (either 90.degree., 180.degree. or 270.degree.) to allow a different set of holes to line up with the exit opening to the carburetor.