Air intakes come standard on every car on the market, and for the most part they do a good job providing enough air to keep the engine both cool and using a healthy air-to-fuel ratio. There are aftermarket air intakes on the market that will provide even more air to the engine, giving it much more horsepower and making it more efficient. These air intakes come in two flavors: the RAM air intake and the cold air intake.
This type of air intake system generally involves an air scoop somewhere on the front end of the car that uses air that is passed through the scoop at higher speeds. Air is forced down through the scoop and into the air box, which increases horsepower and torque at higher speeds (starting at about 40 mph). It is called a RAM air intake because air is rammed into the air box from the forward-facing scoop.
Cold air intakes are very different from the RAM air intake system. The RAM air intake system acquires the air via a scoop that is front facing with the air being forced down into the air box. The cold air intake system is usually located on the bottom part of the front end, and can sometimes be fabricated to be put on the back end of the vehicle. Cold air is sucked into the air box by the engine instead of being pushed to the engine.
RAM air intakes usually are used with bigger engines as they give more horsepower and torque in the lower to mid-range rpm. V8 engines that do not use a turbocharger often are seen with RAM air intakes. These include the Mustang GT and Chevrolet Camaro, as well as the Pontiac Grand AM GT. Bigger engines that do use turbocharger and superchargers often need even more help keeping cool, and do so by incorporating an intercooler.
Many times cold air intakes are used with smaller engines that create more heat because of a turbocharger. Turbochargers can spool up and become too hot if they are not cooled properly, so often both cold air intake systems and intercoolers are used to cool the engine as well as create a much more dense fuel-to-air ratio. Typically, cold air intakes are the better choice when it comes to getting the best ratio of fuel and air, and are used by Nascar, Formula 1 and Grand Prix race cars.
There is slight amount of danger involved with cold air intakes because they are usually located underneath the engine. If for any reason your car is submerged in one to two feet of water, your engine will stop in what is known as hydro-lock. This is a very serious problem that usually results in having to get a new engine.
