MY99-00 WRX/STI CAI with K&N Filter

The Process West Cold Air Intake is a direct replacement for the factory air intake on the 1999–00 WRX and STI, engineered to reduce intake restriction and improve airflow into the EJ engine.

Improved intake sound.

Replacing the factory air box with the Process West Cold Air Intake delivers a noticeable improvement in intake sound. The less restrictive airflow path produces a more pronounced induction note under acceleration, adding to the driving experience without any additional modification.

Precision engineered construction.

Built from lightweight CNC mandrel bent aluminium tubing with a machined airflow meter mount, allowing the factory airflow meter to be retained without modification. Finished in a clean black coating for a purposeful, factory-quality appearance under the bonnet.

High-flow filtration included.

A K&N high-flow air filter is included with every kit, delivering improved airflow and long-term filtration performance over the factory unit.

Straightforward installation.

Designed as a direct replacement for the factory intake with no cutting or permanent modification required.

An effective intake upgrade for the 1999–00 Subaru WRX and STI.