Heat is the enemy of power. You know that, right? Heat robs density from an engine’s incoming air, diluting the impact of combustion, which ultimately costs horsepower. Heat is bad, mmmkay? To make power, you want air, lots and lots of cool dense air, mixed with a healthy swig of high-quality fuel. Unfortunately, one of the prime means of packing more air into an engine—turbocharging—also creates a tremendous amount of heat in the incoming air charge, stealing away some of the turbo’s pressurizing benefits.