ROCHESTER Models M4MC & M4ME 4-Barrel: Description

The M4MC carburetor is a two stage type of downdraft design. The primary side has a triple venturi system. The secondary side is composed of two large bores using the air valve principle, in which fuel is metered in direct proportion to amount of air passing through the secondary bores. A baffle is attached to the secondary side of the air horn above the main well bleed tubes to deflect incoming air to improve secondary nozzle operation on heavy acceleration. This model uses the bowl-mounted choke housing with thermostatic control assembly. For light-duty emission vehicles model M4ME is used, which is basically the same carburetor, except for the deletion of the aneroid cavity and the use of an electric rather than hot air choke.