So you have a downpipe, test pipe, and cat-back exhaust on your EVO and you want more power. If you still have the stock o2 housing, do yourself a favor an upgrade to this high flow invidia unit. The invidia o2 housing flows much better then the stock housing and most aftermarket housings. After installation you will notice a quicker turbo spool and more HP throughout the RPM band.

This Fits: Mitsubishi Lancer Evolution 9