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Understanding Mustang Cold Air Intakes (CAI) and Ram Air Intakes

Understanding Performance Air Intakes

Cold Air Intakes

If you’ve ever put your hand near a running or recently turned off engine, you know how hot they get. Now imagine that heat running through your stock air intake, into your engine, and through your exhaust pipes. Not a very nice picture, is it?
The Mustang’s stock intake was designed to be the quietest piece in the engine compartment. This is great for the driver because it decreases the amount of noise being put out, but it comes with a price. The location of the stock intake in the engine compartment means that the Mustang isn’t running as efficiently as it could be because:

  • The intake tube has a number of bends and turns, so the air doesn’t flow as freely as it could.
  • The air pushed through the intake tube is heated by the engine.
  • Because the air is heated, the volume decreases, and the amount of air being drawn into your combustion chamber is less than ideal. Therefore, your engine's combustion mixtures are not burning at maximum efficiency, which decreases the amount of power put out.

Replacing your stock intake with an aftermarket Cold Air Intake (CAI) will take care of these issues by:

  • Relocating the air box from the engine compartment to the wheel well, so cooler air is being drawn in.
  • The larger intake tube increases volume of air being drawn into the combustion chamber, which allows for better burn. Better burn means more power.
  • The shape of the tube allows air to take a more direct route.
  • The air filter is higher quality and less restrictive.

 

Parts of the Cold Air Intake

Air Filter - Usually conical in shape, with grooves and folds.

Some of the benefits of an aftermarket performance filter include:

  • Though it can look smaller than the factory filter, it has more surface area than the stock filter, which allows air to be drawn in from every direction.
  • Most aftermarket filters are reusable, and only need cleaning every 30,000 to 50,000 miles. The stock air filter needs to be changed every 15,000 miles, and must be thrown away.
  • Aftermarket filters draw in a higher volume of clean, cool air. It's already been established that cleaner, cooler air equals extra power, improved acceleration, and better gas mileage.

Intake Tubes --  Specially designed to straighten air flow as much as possible, while
looking good in your engine compartment.

  • Aftermarket pipes are typically mandrel-bent so there is no crimping of the pipe diameter at the bend.

How much horsepower will my Mustang gain from cold air intake?

The question on everyone's mind is how much horsepower you'll gain from swapping your stock intake for an aftermarket one. There are manufacturer's that will promise a gain of 15-20 hp, but that's a bit of a stretch.
The typical power increase is 5-10 hp.

 

Ram Air Intakes

CAI-2

Much like a cold air intake, the Ram Air Intake (RAI) pulls in cooler air from outside the engine compartment. Unlike a CAI, though, the Ram Air uses a shorter tube, which causes the air to be pushed into the throttle body with much greater force. There is a larger volume of air which, in turn, leads to more engine power.

As you increase the speed of your mustang, wind pressure is forced through the intake manifold and filter. It’s almost like having a turbo charger, but without the additional parts. The downside to the Ram Air is that it will not be very noticeable until you are traveling more than 35 miles per hour.

Other than those differences, the Ram Air Intake is the same as a Cold Air Intake.

How much horsepower will my Mustang gain from Ram Air Intake?

            Just like a CAI, the typical power increase is 5-10 hp.

                                    
Cold Air Intake (CAI) Vs Ram Air Intake (RAI)

Here is a quick Pros & Cons list to help you decide which is better for your mustang.

Ram Air Intake: Also known as a Short Ram Intake. This type of intake uses the straightest possible tubing with a large filter with heat shield to get the maximum air flow. Does not go into the fenderwell.


Pros: Pulls in more air, usually cheaper due to less piping.


Cons: Air pulled in is warm from the engine compartment.



Cold Air Intake: Uses a curved pipe to go in and sometimes down the inside of the fender to pull in air that is not heated by the engine. Uses a smaller filter than a Ram Air Intake and will not pull in the same volume of air as the Ram Air Intake.


Pros: Pulls in cold air for better combustion.


Cons: Pulls in less air, usually more expensive.