Subaru STi Performance Exhaust - HKS - Hiper - `04-`07. This genuine HKS Hiper exhaust is a direct-fit cat-back option for 2004–2007 Subaru Impreza WRX STI owners looking for a higher-flow aftermarket system and a more engaging exhaust note.

Designed by HKS for the Hiper line, this exhaust balances improved flow with street-friendly manners. Construction typically features durable stainless components and mandrel-bent piping to reduce restriction and preserve fitment. The result is a fuller, more aggressive tone without extreme rasp, and a bolt-on installation that works with the factory hangers and mounting points on the specified STi model years.

Features

• Application: fits 2004–2007 Subaru Impreza WRX STI (HKS Hiper series)
• Stainless construction for corrosion resistance
• Mandrel-bent piping for smoother exhaust flow
• HKS-designed muffler for a deeper, sport-oriented tone
• Bolt-on fitment using factory mounting locations

If you have questions about fitment or compatibility, please call us directly — we’re happy to help. We have two installation and customization shops in Austin, Texas and the Los Angeles, California area and can install this exhaust on premises. Call: 512-982-9393 (TX) or 562-981-6800 (CA). If you’re considering purchasing multiple items, contact us for possible shipping discounts. We install on premises at both locations.

CA Residents: WARNING: Cancer and Reproductive Harm - www.P65Warnings.ca.gov