Air Flow Measurement

[Robert McElroy]

	What methods have been used to measure intake air flow other than the =
heated-wire sensor and the Bosch air-flap (that silly door thingy just =
ahead of the throttle plates.)

	Specifically, I am wondering if anyone has looked into using a =
differential-pressure manometer to calculate air flow.  This manometer =
could be located in the same location as GM puts its heated-wire =
mass-air-flow sensor.  Any thoughts/comments?

(FYI - Air flow could be calculated from a differential pressure =
manometer by measuring air pressure in an appropriately sized (perhaps 4 =
inch dia.) venturi located before the throttle plates.  Air velocity =
through the venturi throat is related to the difference in pressure =
between the venturi throat and the pressure before the venturi.  Air =
velocity is thus used (along with air temperature) to determine total =
air mass flowing into the intake system.)

Bob McElroy