Understanding What Cold Air Intakes Do

Gearheads are always looking for new mods to squeeze any amount of extra power or performance out of their vehicle. One such mod that is very popular is the cold air intake, about which aftermarket parts manufacturers make some pretty lofty claims for a relatively inexpensive component. Manufacturers tell you that it increases horsepower, improves throttle response, and provides better gas mileage with a simple and fast installation. For drivers who think this is too good to be true, an in-depth examination can prove these supposed benefits. If you're wondering "what does a cold air intake do?" learn about the advantages of this effective aftermarket mod.

How Does a Cold Air Intake Work?

As a combustion engine, your car or truck’s engine uses what amounts to a controlled explosion to fire your pistons. Gas or diesel serves as the fuel while an ignition source (spark plug in a gas engine, compression itself in a diesel) provides combustion. Oxygen is present in the air that surrounds your vehicle, but the enclosed nature of your hood prevents it from easily getting into your combustion chambers. The air intake is simply ductwork that allows the engines vacuum to pull air into the engine to mix with fuel and be fired. How much air it can pull is what’s the question.

While the OE model air intake works fine, it has the same problems as most stock parts. It’s cheaply made to keep costs low and it’s not specifically geared toward performance. After all, motor vehicle manufacturers don’t know if you’re buying their machine to commute to work, haul cargo, or drive fast. Secondly, because consumers generally care about a quiet, noise free cabin, intakes are designed to be quiet, which, similar to exhaust, often makes them very restrictive.

Your typical stock unit has two main issues preventing it from operating efficiently. First, it’s design is not catered to flow the maximum amount of flow (or CFM) possible. Secondly, it’s design is simply to provide a quiet, efficient passage of air to the engine that the driver in the cabin cannot hear. OEM intakes generally have a filter box and duct work that is restrictive. This means air has to travel through the box, through the mesh of the filter, and through the restrictive tube to get to your engine. This is only made worse by the low-flow air filters you find in most cars and trucks. Couple that with an intake that’s too close to the engine, drawing hotter air, and you have decreased performance.

A cold air intake moves the intake point farther away from the engine, so it sucks in cooler air. Some of them also include a high-temperature shield to further reduce the heat radiating from your internal parts. By removing the air box , reducing restriction in the ducting, and getting rid of the low-quality paper filter, you create an intake that can flow more air per minute to the engine.

Your vehicle is now using colder and denser air to run your powerplant. The denser the air, the more oxygen gets to your engine. This makes it operate more efficiently, providing a host of performance benefits.

What Are the Advantages of a Cold Air Intake?

Do cold air intakes work? The increased oxygen flow can net you between 5 and 20 horsepower depending on your engine and the product you buy. Higher quality intakes obviously work better, but they can’t turn a 4-cylinder into a V8 power, so keep your expectations realistic.

Beyond the horsepower increase, cold air intakes can also provide better throttle response and improved fuel economy. When your engine has the ability to get more air, it has the ability to create more power.

Another plus of an aftermarket air intake is saying goodbye to low-quality paper filters. Not only can you install a high-flow filter, it also means don’t have to replace it every 15,000 miles. Many of the filters available for cold air intakes can be removed and washed to clean them. Just remember to do it as part of your regular maintenance: a dirty filter won’t do its job.

To increase the benefits of your install, consider adding a few other mods to your machine. The air intake is only one side of the oxygen coin. Spent gases can choke off your engine, preventing the cold air from being as effective. A performance exhaust system removes more of these gases from your engine, allowing for better combustion. An ECU tuner can provide a better fuel/air mixture to get the most from these components. Combining all 3 together – air intake, exhaust, and an ECU tune is generally referred to as “Stage 1” in the tuning and modification world – it’s the first and most basic steps to getting increased performance.

That isn’t to say you need either of these additions to gain the benefits of a cold air intake. You still have denser air providing more oxygen to your engine. These mods just add to the advantages of the component.

Do Cold Air Intakes Cause Problems?

There’s a lot to recommend cold air intakes, but every mod has its minuses. Newer vehicles often feature more complicated components. Manufacturers generally limit the mods you can install to limit liability. In the case of an aftermarket air intake, this means the part may void your warranty. Check your warranty to see if this is true for your car or truck.

The lack of a box increases the chances your intake could suck up some water. Small amounts can cause misfires, ruin spark plugs, and reduce performance. If a larger volume of water gets into the combustion chamber, it won’t compress under the piston, causing severe engine damage. For driving in wet areas, you should install a bypass valve on your air intake to prevent water from getting into your engine.

The shape of the intake occasionally causes problems as well. The air is coming from a difference angle than it is on an OE model, which can throw off the idle of your engine. It can also send inaccurate readings to your sensors, throwing off the fuel/air mixture. This issue is fairly rare, however, and can often be fixed with some tuning.

Finally, cold air intakes do not take into consideration, much like performance exhaust, that additional sound can be an issue. In most vehicles, you will immediately hear a sound with a cold air intake you didn’t hear before – the sound of air sucking or flowing through the intake! On vehicles with a turbo, this sound is often much more pronounced. For some owners, this sound, much like a well tuned, throaty exhaust is desired. For others, it may be considered too much.

Overall, the answer to the question “do cold air intakes help with performance?” is yes. These parts may have a few sticking points, but they are nothing compared to the advantages you can gain. Instead of the all-weekend installation of some aftermarket parts, you can get a new cold air intake in a few hours. If you have solid experience and a few handy tools, you can even do the work yourself. Check out your local AutoZone or shop online for some of the top performance air intakes for your specific make and model.

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