air coming in the front of the mail slot or the grills isnt going to just push out cold air, it'll push any and all air sitting in its way out the engine bottom.
The difference in hot and cold air is the density, but when a 60 to 90 mph airstream hits stagnant air, the higher velocity air is going to win > wheater its hitting cold or hot air. It'll also go the path of least resistance, i.e. towards the nearest open hole, so >> some toward higher openings, the rest towards the engine bottom.
Again, this is not a closed system; why over analyze it? If you want to spend 199.00 on this knock yourself out.
As the last commenter said, your're messing with the drag coefficients w/o knowing what you are doing. My point was Chevy DID wind tunnel testing, as the SS yeilds 160 lbs of upforce while the ZL1 has overall downforce (65?? lbs).
Frankly why mess with Chevy"s work unless it yields a way of feeding a CAI box directly, like the old shaker hoods, or directly to the TB thru a straight vararam style intake? That would get my money in a hurry.