You don't want to overdo things. There is positively no sense in running too rich and it is dead easy to do.
High CFM carburetors run too lean, not rich. They flow plenty of air, and not enough fuel, due to the low velocity of air through the venturis not generating enough vacuum to siphon the fuel out of the float chamber and through the main jets. That's why engines with "too big" carburetors have a tendency to stall, stumble, pop, backfire, and leave big blistered spots in the paint on the hood when a backfire starts a fire in the engine compartment!
Jerry
