And it's all responsive to airflow ,yes,? The higher the airflow the more difference in pressure?...Without airflow a carburetor does nothing...
Have it your way........but the venturi is really the key......no matter the airflow, no venturi, or equivalent shape to affect airflow, no pressure drop. Ray
But, with out atmospheric pressure and pressure differences, there is no air flow. For a carb to function it needs both . Bones
"The Venturi effect is the reduction in fluid pressure that results when a fluid flows through a constricted section (or choke) of a pipe. The Venturi effect is named after Giovanni Battista Venturi (1746–1822), an Italian physicist." from Wikipedia (whomever he is)
I bought my '69 Camaro in 1973 and it came with its own bs story: The previous owner told me he had modified the car to turn 10 seconds in the quarter mile. I worked in the machine shop that had rebuilt the engine and I had actually done the valve job on the heads. Nothing special had been done to the engine. I bought the car and started to "undo" his special mods. The car got about 6 mpg due to him disconnecting the vacuum advance. I discovered why he disconnected it. He had been connecting the hose to the wrong port on the Holley. I spent about a month correcting his fixes. I never could get the 255hp 350 with TH 350 to turn anything resembling a "10 second" car!