If warm air was so good for an engine, why do OME's go to all the trouble to draw air from outside the engine compartment? Why do turbocharged systems use intercoolers? Because colder air is denser, therfor you can pack more in, and colder air is less prone to detonation and pre ignition. Also I have what I consider is a TRUE cold air intake: a Snorkle system. For clean "cold" air, look at a snorkle.