Are you looking for an air intake but aren't sure which one to buy?
There are different styles of Air Intake for you to choose from, such as Long Ram Cold Air Intake, Short Ram Air Intake, and Ram Air Intake kits. Here is a description of what they are and how some of these systems work...
Long Ram Cold Air Intake Systems:
Long Ram Cold Air Intake Systems create more horsepower and greater gas mileage by increasing the volumetric efficiency within the cylinders. The efficiency is increased due to removing the restrictive stock airboxes and replacing them with smooth flowing, mandrel bent tubing. This increases the amount of air and the velocity of air flowing into the engine. The air going into the engine is also significantly cooler (and denser) on a cold air intake system because the air pulled into the intake is pulled from air that is further from the engine that has not been heated as much. The filters are also more efficient, allowing more air into the intake.
Short Ram Air Intake Systems:
Short Ram Air Intake Systems are very similar to the long ram counterparts, but they have much shorter tubing than the cold air intake systems. They are typically not as efficient as a long ram cold air intake system because they pull in air that is closer to the engine, which is warmer and less dense. They still significantly out perform most stock air intake systems.
Ram Air Intake Systems:
Ram Air Intake Systems use outside air to force induction into the engine. You may see a ram air intake kit on a car with a scoop on the hood. The air enters the intake through tubing attached to the scoop. As the vehicle speed increases, the air velocity coming into the intake also increased. This essentially creates "boost" at high speeds, creating good cold, dense, high velocity air in the engine, creating more horsepower. Some Long ram systems are trying to capitalize on this type of "forced induction" by getting the air filter down low enough to reach the high speed air coming through the front bumper.
Cold air intakes add horsepower by increasing the air available for the engine, and improving the air that the engine receives. How do you know you are getting the best one, and what is the difference in the different brands and designs? There are several things to consider when looking at an air intake. The best thing to do it to look at the dyno proven results. These (typically) are an accurate representation on how it will perform on your vehicle. We have to assume that the only change from the first run to the second is the air intake, and that other "cheater" additions have not been made, such as a performance chip, etc. Assuming the dyno results are accurate, these are a good point for comparison.
Many have fallen victim to believing that bigger is better when considering and air intake system. This is true in some cases, but not in others. Consider the straw analogy. As the straw diameter increases from zero diameter, the amount of air/fluid allowed through the straw will increase, but only up to a certain point. There is a point where the straw diameter increase will negatively affect the amount that can be passed through the straw because the force pulling it through has not increased (this would be equal to the cylinder displacement remaining constant.) On the smaller import engines, sometimes the dyno proves that a 2.5 or 2.75 inch diameter intake can outperform the larger 3 inch diameter intake. This is of course a product of the tubing length and diameter, as well as the flow of the actual filter.
If that didn't make sense, don't worry. Trust the dyno results. Some intakes claim huge maximum power gains, but these "maximum" horsepower gains should be treated like the max output of an amplifier... you might see the maximum gain only under ideal conditions (such as accelerating downhill into the wind at 6500rpms, or in the example of the amplifier, it is struck by lightning.) The real output gains are somewhere near the middle to bottom half of the actual range for most tuners and drivers.