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This should explain the proper workings of your 7044206 R4-4MV Quadrajet. TimAT and Metalkid are on the right track.

The secondary metering system supplements fuel
flow from the primary stage and operates as follows :

When the engine reaches a point where the primary
bores cannot meet engine air and fuel demands, a lever
on the primary throttle shaft, through a connecting
link to the pick-up lever on the secondary throttle shaft ,
begins to open the secondary throttle valves . This occurs
only if the choke has warmed the thermostatic coil
sufficiently to release the secondary throttle valve lock -
out lever (if used).
As the secondary throttle valves open, engine manifold
vacuum (low pressure) is applied directly beneath
the air valves. Atmospheric pressure on the top of the
air valves forces the air valves open against spring and
air valve dashpot forces, provided the choke coil has
warmed sufficiently to release the air valve lockout lever,
if used. This allows air to pass through the secondary
bores of the carburetor.

Service Manual Models 4MV-4MC-M4ME-M4M C