Holley running rich at part throttle cruise
Change the primary air bleeds go 2 sizes bigger or drill them if yours are not threaded.. Or you can pull yours and thread the holes , there is a kit for that. Also Drill 3/32 holes in all 4 of the venturi valves. This will make a big difference if you don't have a 4 corner idle circuit carburetor. You probably are out of square on your transfer slots.
Change the primary air bleeds go 2 sizes bigger or drill them if yours are not threaded.. Or you can pull yours and thread the holes , there is a kit for that. Also Drill 3/32 holes in all 4 of the venturi valves. This will make a big difference if you don't have a 4 corner idle circuit carburetor. You probably are out of square on your transfer slots.