Pressure: You are not taking into account that a recirc valve lets down the pressure of the air charge as well. Just because its dumping back into the beginning of the intake track instead of to atmosphere doesn't mean you aren't still taking a pressure drop across the valve. In fact if you want to get technical, the pressure at the point in the intake where recircs dump in to is on the suction of the compressors and is in fact slightly less than atmospheric pressure.
Temperature: Another thing you haven't thought of is that the air that the recirc valve returns to the intake tract is HOTTER than atmospheric. With blow off valves the lost air is displaced with fresh cool air. Atmospheric air will always be cooler than air that has been compressed and intercooled.
Z-Jay Vice President - Edmonton Z Car Club 93 300ZX TT - Stage VI
21:13:33 08/15/06
