Borla 04-07 STi XR-1 Cat-Back Exhaust

This Borla XR-1 S-Type cat-back exhaust system is what you get when you want a more aggressive sound and improved performance for your 2004-2007 Subaru Impreza WRX or WRX STI. It's a complete system that bolts directly onto your existing exhaust hangers, replacing the factory muffler and piping from the catalytic converter back. Inside the muffler, you'll find Borla's patented XR-1 multi-core technology, designed to increase exhaust flow significantly. This means more power, especially when you tune your turbocharged engine, and it can even help with fuel economy.

Borla builds this system using T-304 austenitic stainless steel, which is a strong material that resists corrosion better than other types of steel. The tubing is 3 inches in diameter, leading to a polished 4-inch angle-cut tip with a rolled edge and the Borla logo embossed on it. This system is designed as a direct bolt-on, meaning no welding or cutting is required for installation. It meets all emission requirements, so you can install it without worrying about emissions compliance.

Borla backs this exhaust system with a written million-mile warranty, reflecting their confidence in the product's durability and performance. If you're looking to enhance the sound and power of your Subaru, this Borla cat-back is a solid option. For even more performance gains, Borla suggests pairing it with their header part number 17217.