K&N 02-07 WRX/STi 57i Performance Intake Kit

This K&N 57i Performance Intake Kit gives you a large, washable K&N air filter along with the necessary adapters to connect it directly to your Subaru Impreza's throttle body. It's designed to replace the restrictive factory air box, allowing your engine to breathe more freely. This setup is intended to provide a power increase across the entire RPM range, making your car feel more responsive.

The open-air design of the K&N filter offers more surface area than a standard filter, which means even more airflow with less restriction. This larger filter can also hold more dirt, extending the time between cleanings – K&N claims up to 100,000 miles before needing service. The adapters are made from durable materials like steel and aluminum to ensure they hold up over time. K&N backs this kit with their Million Mile Limited Warranty.

Keep in mind that this intake system is not legal for sale or use in California and other states that have adopted California's emissions standards. You'll want to check your local regulations before purchasing.