You have it narrowed down to a science... :bill:
+1 for what JP just posted.jpark said:The way manufacturers design the systems feeding, operating, and monitoring the engine and transmission, my guess is that any extra air will just be compensated and adjusted by the PCM, and that the extra air intake will just add dirt to the intake system.
Manufacturers now spend a lot of money designing systems to get every last MPG and HP/torque out of every drop of fuel. They test powertrains in every possible environment -- hot, cold, dry, wet, and in different altitudes. Unless you add a turbocharger or supercharger, my guess is that modified intakes don't really do anything anymore (other than allow more dirt to enter the system), and you're better off just leaving the factory system alone.
Just my .02.