incorrect. 6psi is 6 pounds of pressure on every square inch of surface area. RBs have equal volume runners, that means that each runner holds the same volume of air being fed from the plenum. the same volume of air, under the same pressure fed through the same size hole will funnily enough flow the same amount of air as the next hole.
planes fly because there is a speed differance over the aerofoil. the air is forced to travel faster over the top of the wing by the convex shape being a further distance to cover then the concave bottom. this creates a high pressure on top of the wing and a low on the bottom. the low pressure tries to equalise with the high, acting on the bottom of the wing, pushing it up.
i dont think nissan would have spent millions of dollars developing the SR20 engine to have lean as No 4 cylinders.
what you are saying would be true if we where talking about NA engines but as soon as you add boost it throws it all out the window.
the engines i work with are 27ltr, twin turbo V12s that make around 1000hp at 30psi, carrying 100 tonnes of rock up a steep hill of around 2km in length for 12hrs a day in upto 45deg heat. the outlet of the aftercooler is right at the rear of the engine, around 1.5mtrs from No1 cylinder compared to 5cm to No12 and AFRs are the same across ALL cylinders.