Enhance your Subaru STI’s performance with the K&N drop-in air filter designed to boost horsepower and improve airflow. This high-flow air filter for the Subaru STI is crafted with layered, oiled cotton media that not only increases performance but is also washable and reusable, ensuring lasting quality backed by K&N’s 10-Year/Million Mile Limited Warranty.

Key Benefits

• Improved airflow for better engine efficiency
• Increased horsepower and quicker acceleration
• Washable and reusable design for long-term savings
• Supported by a solid 10-Year/Million Mile Limited Warranty

Easy Installation & Compatibility

This K&N air filter for the Subaru STI is designed as a perfect drop-in replacement for your factory air box. Its straightforward installation makes it ideal whether you’re an experienced enthusiast or just getting started with vehicle upgrades. Specifically engineered for Subaru fans, it fits models such as:
• 2004 Subaru Impreza WRX STI

For additional technical details, please refer to our Technical Bulletin.

Upgrade your ride and feel the difference—buy the K&N drop-in air filter today and experience the superior performance every Subaru STI owner deserves. For more premium air filter options, visit our Air Filters - Drop In collection.