Zenith Carburetor CFM?

[Bob Bidonde]

My speculation is the Model A needs to breath 100 CFM in stock form. I base this on the engine's volumetric efficiency.

100% Volumetric Efficiency means that the engine can breath its total displacement in one combustion cycle. So for 200 cubic inches, and assuming the "L" head engine has a 50% Volumetric Efficiency, the carburetor needs to be capable of 100 CFM

Does anyone know the CFM of the Model A's Zenith carburetor?