I've seen that EM episode, you have to take these things with a large grain of salt guys FB is a smart guy but these tests hardly control all the variables etc and are only representative of their one test setup (in this case a BBC with huge heads, a huge intake and relatively short runners). Colder air makes more power, less heat transfer through the intake tract to the air, makes more power. Cold fuel may also play a part, but saying a cooler intake makes no difference is a bit misleading IMO despite what they 'saw' in the episode.