If you really want to see the airflow differences between the port and stbd sides of an aircraft fly with the doors off.
Years ago I flew in the back of a Scout doors off. On one side you could hardly breathe due to the force of the rotorwash added to the fwd airspeed, on the other side a hell of a lot less.
Must have the effect of "supercharging" one side on a 76.
The intake position must be an important factor. No doubt the aerodynamacists can give us an answer.