Are cold air intakes a total waste of money? See, the idea is that colder air is denser and contains more oxygen, which gives you more power when it mixes with fuel. A cold air intake pulls that cooler air into your engine. However on most stock cars, the power gain is actually very small and barely noticeable, since modern factory intakes are already so efficient. But let’s be real, you’re just after that sweet sound and a much cooler look under the hood.