Air Intake Systems: What, Why, and Are They Worth It?

What Are Air Intake Systems?

Air intake systems, often called cold air intakes, are popular performance modifications installed on all vehicle classes, ranging from high-performance sports cars to hard-working diesel trucks. These accessories replace your vehicle’s factory intake assembly with aftermarket intake tubes, air boxes, and filters to overcome restrictions in the intact tract, thus allowing more air to enter the cylinders.

How Do Air Intake Systems Work?

Air intake systems operate on the notion that more intake airflow = more power—and this concept isn’t far-fetched. An internal combustion engine works by correctly timing and harnessing the energy produced by detonating a mixture of air and fuel inside a cylinder, thus creating the momentum necessary to rotate the engine. As a crucial component of combustion, alongside fuel and ignition, airflow is a requirement for an engine to run. 

Air intakes utilize components like large-diameter mandrel-bent intake tubes, oversized air filters, heat shields, and sealed air boxes to ensure the maximum flow of cool, dense air into the intake, thus producing a powerful and efficient combustion event. In other words, air intake systems allow the engine to inhale more fresh air to produce more power. In most cases, aftermarket intake systems net dyno-proven gains of anywhere from 5 to 20 horsepower.

Air Intake System Configurations

Air intake systems come in several configurations, including filter construction, intake tube materials, and air box designs. Let’s take a look at these options.

Air Filter Designs

Air filters come in several configurations, ranging from traditional dry, single-use paper filters to reusable oiled filters. But what are the benefits of each?

Paper Air Filters

The paper air filter is perhaps the most common type on the road today. Original equipment in most vehicles, this style of air filter provides an excellent balance of affordability and functional filtration. Paper air filters are intended to be replaced every 5-10 thousand miles. While more affordable than other designs, the cost of replacing paper air filters can add up over time.

Reusable Air Filters

The advantages of reusable air filters over paper are considerable—they are washable, free-flowing, and long-lasting, and they are an easy upgrade for most vehicles on the road. One of the most popular manufacturers of reusable air filters is K&N. With proper maintenance, K&N’s reusable air filters, featuring an oil-impregnated design, will likely outlive your vehicle. However, reusable air filters must be oiled every 5000 miles to retain efficiency and filtration properties.

While oiled cotton air filters are perhaps the most popular reusable car air filter design, other manufacturers use a dry, synthetic weave, which requires occasional cleaning with a proprietary cleaning solution. Both oiled and dry styles of reusable air filters are frequently used in air intake systems.

Intake Tube Materials

Air Intake tubes also vary by air intake manufacturer, with the two most popular materials being metal (typically aluminum) and composite (typically polyethylene). 

Composite intake tubes are usually manufactured from high-density polyethylene plastic. While plastic may evoke thoughts of poor quality, thermoplastic polyethylene combines lightweight flexibility with outstanding durability. The material is even used in certain bulletproof vests. This composite material is more than capable of withstanding conditions under your vehicle's hood.

From a performance standpoint, composite has a couple of advantages over metal. First, composite material doesn’t retain as much heat as metal, meaning your plastic tubing doesn’t run as much risk of heating the air entering your engine. Second, the composite molding process allows for precisely engineered bends more than a metal intake. This allows the air to flow freely into the intake manifold, reducing turbulence and improving power over traditional metal tubing.

Intake Air Box Designs

Lastly, let’s discuss intake air box designs. From the factory, most manufacturers employ sealed air boxes with integrated air scoops that funnel air from outside of the air box under the hood. As a result, most high-quality manufacturers opt for similar designs—in most cases, if the original manufacturer does it, it’s probably best to take notes. 

This being said, not every manufacturer includes a premium molded airbox. In some cases, manufacturers simply affix an air filter to a bare intake tube, which sucks hot air directly from the engine bay. While this design may look impressive, it may actually hinder performance, especially on hot days. Our recommendation, especially for street-driven vehicles in warmer climates, is to opt for an air intake system with a factory-style sealed air box.

Are Air Intake Systems Worth It?

So, are air intake systems worth the money and hype? Undoubtedly, yes. These systems undergo loads of R&D testing to ensure maximum efficiency and dyno-proven performance gains you can not only feel but hear. 

One of the most significant benefits of an air intake system is its effect on sound, as the larger filter and larger-diameter intake tube produce a noticeable grumble, or growl, from the engine compartment. Especially when paired with an aftermarket exhaust system, an air intake system is worth its weight in gold.

RealTruck Recommended Air Intake Systems

Now that we’ve determined air intake systems are worth the price let’s check out our top-recommended systems. Each system on this list has been hand-selected to offer the best blend of performance, sound, ease of installation, and quality.

S&B Cold Air Intakes

As an industry leader in the aftermarket air intake department, S&B knows a thing or two about airflow. The company’s proprietary Cold Air Intake is a staple in the performance industry, especially for diesel truck applications. 

Featuring rotomolded composite intake tubes, heavy-duty silicone intake couplers and tube seals, an oversized sealed intake box, and your choice of 8-layer, washable, oiled-cotton, or dry replaceable filters, S&B Cold Air Intake systems offer outstanding performance. Plus, the clear inspection window makes for a stylish addition to any engine bay.  

Features: 

• Increase horsepower and improve fuel economy

• Heavy-duty silicone intake couplers and tube seals

• Simple DIY installations

• Available with 8-layer, washable, oiled-cotton or dry replaceable filters

• Oversized, fully-enclosed air box

• Clear inspection lid to monitor the filter's condition

• Filters are tested to ISO 5011 Filtration Standard

• Backed by a million-mile warranty

• Made in the USA
  
  

K&N 77 Series High Flow Performance Metal Air Intakes

If you just can’t stray from the aesthetics of metal intake tubing, consider a K&N 77 Series High Flow Performance Metal Intake. This premium intake system utilizes mandrel-bent alloy tubing for smooth, unrestricted airflow into the intake manifold. K&N’s reusable oiled-cotton air filter provides maximum filtration to keep your engine healthy and clean. 

This product features a vehicle-specific design for a simple installation. Vehicle-specific mounting tabs align with factory-threaded holes for a quick bolt-on install. K&N also employs a metal heat shield with a pre-installed bulb seal, sealing against the hood to prevent hot engine bar air from entering the filter. 

Features: 

• Available with a polished or silver intake tube

• Mandrel bent tubing eliminates restrictions

• Guaranteed to boost horsepower and torque

• Vehicle-specific design for maximum performance and ease of installation

• Reusable air filter

• Mounts using factory holes for quick installation

• Oversized conical air filter improved airflow into the intake

• Compatible with OE computer systems

• Backed by a one million-mile warranty

• Some kits may not be legal in CA

Rugged Ridge Cold Air Intake

Treat the off-road rig in your life to the unmatched performance of a Rugged Ridge® Cold Air Intake. This premium intake system utilizes a mandrel-bent, polished aluminum intake tube for smooth, unrestricted airflow into the intake manifold. Rugged Ridge’s black, powder-coated heat shield prevents engine heat from entering the included dry air filter, adding up to 10 horsepower and 12 lb-ft. of torque.

Features: 

• Polished aluminum intake tube

• Black powder-coated heat shield

• Dry filter requires no oiling

• Adds up to 10 horsepower and 12 lb-ft. of torque

• 50-state legal

• 5-year limited warranty