My personal answer to cooler air for intake, was to use an AEV snorkel ! Most States, most of the year, in spite of heat (index) , outside air temps are going to be cooler than any supply under the hood of a working engine. I went with AEV because it was the easiest install. Least invasive. A large air supply line. And just as important to me, the least number of "restriction-elbows" in route. One other thing I do during the warmer months is to take off the visual shield-cover on top of the engine so as not to additionally trap unwanted heat. (In my case, I gained 1/2 mpg in the city. FWIW). Another approach is a vented hood for heat reduction. Again, I went AEV because of the snorkel ready fit option.One other debate. Is keeping, replacing, or removing all together the air dam-spoiler underneath the front bumper. Its there to create negative pressure allowing more air flow thru the radiator, etc etc. In addition, I too have a dry K&N air filter.....CAI is relative I suppose to how far u wish to take the whole scenario. Best of luck .
