High Flow Air Filters: Are They Really Better?

High flow air filters can increase your engine's horsepower by 3 to 5 HP and torque. Learn more about how they work and their pros and cons.

High Flow Air Filters: Are They Really Better?

When it comes to air filters, the debate between high flow and low flow is a common one. Many people believe that high flow air filters are better for their engine, but is this really the case? In this article, we'll explore the pros and cons of high flow air filters and how they can affect your engine's performance. It's true that a high flow air filter can increase your engine's horsepower by 3 to 5 HP and torque. This is because more air is able to enter the engine, allowing it to perform better. However, this increase in power is usually quite small and you may not even notice it.

High flow air filters are also more effective at removing particles from the air as they enter your HVAC system. This means that they can improve the air quality in your home and keep your lungs healthy. However, these filters require more energy and effort from your HVAC unit to use them. The increase in airflow resistance that comes with a high-efficiency filter is usually marginal, though it can vary depending on your home and HVAC system. It's important to note that the ratio between filtration efficiency and resistance to airflow is not linear.

This means that as filtration efficiency increases, resistance to airflow does not necessarily increase at the same rate. For example, Second Nature's Essential filter is 450% more effective at trapping particles than a cheap, low-efficiency fiberglass filter, but its resistance to airflow is only 20% higher. High performance air filters are also known as high-flow air filters. You may have seen these at auto parts stores, claiming extra power and more torque than the factory filter. These new filter designs are made of a filter media that has an inherently high mass airflow handling capacity and often come with an optional ducting and housing assembly. What Fenske doesn't prove is how well each aftermarket filter actually filters the air entering the engine compared to the original unit.

It suggests that the increase in power could be the result of less filtering, especially in the case of the cheaper CarQuest filter. Low-efficiency filters are generally within MERV 1-4 and high-efficiency filters are MERV 13 and later. It takes time for a filter to charge sufficiently to have a beneficial effect, so that everything that passes through the filter ends up in your system or in your home. Many high flow air filters generally increase the power of your vehicle between 5 and 10 horsepower; however, some very high performance high flow air filters can add up to 25 horsepower to the output of your car's engine. He finds that on the test bench, aftermarket filters actually produce more than the OEM unit, with the largest gains produced by the K&N filter (around four horsepower and five pounds).