High-Performance Air Filters: Do They Really Work?

When it comes to vehicle upgrades, high-performance air filters are often touted as one of the easiest and quickest components to swap out for improved performance. Many companies claim that their designs can increase horsepower, torque, and acceleration. But do they live up to the hype? Let’s dive into the details and find out.

What Is an Air Filter?

An air filter is a critical component in your vehicle’s engine system. It prevents debris and dirt from entering the engine through the intake manifold valves. The engine relies on a clean air-fuel mixture for optimal performance, and the air filter ensures that the air is as pure as possible. By removing not just large pieces of dirt but also fine particles, the air filter helps maintain engine performance and fuel economy while preventing potential damage to engine components.

Types of Air Filters

1. OEM Filters: These are the standard filters that come with your vehicle. They are designed to meet the basic requirements for filtering air and are typically made of paper.
2. Aftermarket Filters: These include performance or sport filters, which are designed to allow more air into the engine, potentially increasing power. They are usually made of higher quality materials such as cotton or foam and are often reusable.

Testing High-Performance Air Filters

To evaluate the effectiveness of high-performance air filters, Jason Fenske from Engineering Explained conducted tests using a Subaru Crosstrek. The filters tested included:

• The original dirty OEM filter
• A new OEM filter
• A low-cost replacement filter from CarQuest
• A high-performance K&N air filter

Each filter was tested using a dyno run to measure horsepower and torque and a VBox to measure acceleration. Here are the results:

• Original Dirty OEM Filter: 158 horsepower, 137 pound-feet of torque
• New OEM Filter: 160.1 horsepower, 137.4 pound-feet of torque
• CarQuest Filter: 163.3 horsepower, 140 pound-feet of torque
• K&N Filter: 164.3 horsepower, 142.5 pound-feet of torque

Real-World Performance

In real-world tests, the aftermarket filters showed minor but noticeable improvements in acceleration. For example, the 20-60 mph sprint times improved slightly with the aftermarket filters compared to the OEM filters. The K&N filter showed the best performance, reducing the 20-60 mph time from 9.01 seconds with the dirty OEM filter to 8.81 seconds.

Advantages of High-Performance Air Filters

1. Increased Airflow: High-performance air filters allow more air into the engine, which can increase horsepower and torque. The K&N filter, for instance, improved the Crosstrek’s horsepower by about 6 hp.
2. Reusable: Unlike paper filters that need frequent replacement, high-performance filters can be cleaned and reused, typically every 10,000 miles.
3. Better Filtration: High-quality filters can offer better air filtration, helping to keep your engine cleaner and running more efficiently.

Disadvantages of High-Performance Air Filters

1. Increased Engine Noise: The larger volume of air can make your engine sound louder, which might not be desirable in all situations.
2. Potential for Increased Debris Intake: Some high-performance filters might allow more dirt and debris into the engine, which could lead to increased wear on engine components.
3. Risk of Water Ingestion: Especially with cold air intakes, water can splash up from the road and soak the filter, potentially allowing water into the engine.

Installation and Maintenance

Installing a high-performance air filter is a relatively simple process. It involves replacing the old filter with the new one, which typically involves unscrewing or unclipping the housing and fitting the new filter in place. Maintenance involves cleaning the filter every 10,000 miles, which is straightforward with a cleaning kit.

Conclusion

So, do high-performance air filters really work? The answer is yes, but with caveats. They do provide modest improvements in horsepower and acceleration and have the added benefits of being reusable and potentially offering better filtration. However, they also come with some drawbacks, such as increased noise and the potential for allowing more debris into the engine.

If you are looking for a simple upgrade that can provide some performance gains and you are willing to maintain it properly, a high-performance air filter could be a worthwhile investment. Just remember to weigh the pros and cons and choose a high-quality filter to minimize risks.