Holley Model 5220 2 Barrel Carburetor

Fig. 1 Holley model 5220 carburetor. 1983:

Fig. 2 Holley model 5220 carburetor. 1984-86:

The Holley model 5220, Figs. 1 and 2, is a staged dual venturi carburetor. The primary bore or venturi is smaller than the secondary bore. The secondary stage is mechanically operated by linkage connecting the primary and secondary throttle levers. The primary stage includes a curb idle and transfer system, diaphragm-type accelerator pump system, main metering system and power enrichment system. The secondary stage includes a main metering system and power system. Both the primary and secondary venturi draw fuel from a common fuel bowl. The electric automatic choke has a bimetal two-stage heating element. The carburetor also has an electronic solenoid and a vacuum-operated bowl vent.