My ONLY point was, In LITERAL terms, a 350ci engine "always" displaces (rather than "consume") 350 cubic inches of air volume every 2 revolutions, irrelevant of whether the throttle blades are cracked, at WOT, the inlet air temp is 500* or -90*;
A 350 cubic inch engine will displace (or ingest) 717cc of air per revolution, regardless of rpm or other conditions.
Using the SAE standard J1349, which is 29.24 inHg at 77F deg, the ingested air mass would be .00092 lbs per revolution.
This would occur at the engine torque peak, not the power peak.
If Standard Temperature conditions are used (29.92 inHg and 32F deg) the air mass would become .00102 lbs per revolution.
This would result in an increase of Volumetric Efficiency of 10.8%.
The air volume has not changed, nor can it change; but the air density has changed, causing a change in air mass and therefore in VE. Obviously, changes in pressure and temperature will cause substantial changes in VE and performance.
Since, for our engine the peak VE occurs at the torque peak, we can call that OUR 100% VE point, and every other torque value, above or below, will represent the relative change in VE. In effect, the torque curve of the engine becomes the VE curve for
that engine; only the units are relative to it peak torque value.
Take any engine rpm vs torque curve, and divide each value by the peak torque and graph the result against rpm. That is the VE curve for your engine. It will change from day to day, perhaps even hour to hour.
But the trick is to improve or raise the curve. How?
We can raise the inlet pressure using inlet tuning or forced induction. Or we can lower the inlet air temperature.
Or we can try to trap the ingested air and prevent its escape due to flow reversion.
Of course, we can change the way the engine burns the fuel. But that is no longer relevant to VE; it then slides into the realm of CE, Combustion Efficiency.