When it comes to engine performance, air is essential. A high-flow air filter can increase your power by 3 to 5 HP and torque, as well as improve fuel efficiency. To test this, a car was tested with a dirty OEM air filter and then with a clean OEM filter. The results showed that the car produced 158.25 hp and 137.25 lb-ft of torque with the dirty filter, and 160.10 hp and 137.43 lb-ft of torque with the clean filter, an increase of 1.85 hp and 0.18 lb-ft.
Although the numbers are small, you may still be able to feel the extra power. In addition, aftermarket filters have been tested in the shop and have been found to produce more power than OEM units, with K&N filters providing the most gains (around 4 hp and 5 lb-ft). However, it is important to note that these filters have not been tested for their filtering capabilities compared to OEM units. Finally, aftermarket filters are made of several layers of cotton filter material treated with oil to help stop contaminants from entering the engine. This could be why they produce more power than OEM filters, as they may be less restrictive. Overall, an aftermarket air filter can increase your engine's power and torque while also providing better filtration than OEM filters. This can help you save money in the long run by not having to buy new filters as often.