Holley Model 6280 2 Barrel Carburetor

Fig. 1 Holley model 6280 carburetor assembly:

These dual venturi carburetors, Fig. 1, use four basic metering systems. The basic idling system provides a mixture for idle and low speed. The accelerator pump system provides fuel needed for acceleration. The main metering system provides an economical mixture for normal cruising conditions. The power enrichment system combines a mechanical and vacuum operated power valve to provide a rich mixture when high power output is necessary. These carburetors also have a fuel inlet system to constantly supply fuel to the basic metering systems and a choke system to temporarily enrich the mixture for efficient starting and running of a cold engine.