If your engine bay air extractor vent is directly on top of the sealed air box then guess what--it's not sealed. The extractor vent is doing exactly what it's designed to do: extracting air directly from the air box that you want packed with air thus depriving your motor of, well, air. Block the vent with heat tape and stop stealing air that the cold air box is supposed to be providing your motor. Dyno numbers are meaningless because they measure hp on a static vehicle. Moving at 75 +...

Steeda CAI - My Personal Heat Extractor Theory