HKS Hi-Power Single Exit Cat Back - 2015-2021 WRX, 2015-2021 STI

HKS Hi-Power Single Exit Cat Back 2015-2021 WRX / 2015-2021 STI | 85mm Diameter | Performance Exhaust System

Overview

The HKS Hi-Power Single Exit Cat Back exhaust system is designed specifically for the 2015-2021 Subaru WRX and WRX STI, delivering a perfect balance of aggressive sound, reduced back pressure, and weight savings. This system replaces the factory quad-exit setup with a single right-side exit featuring an 85mm pipe and bullet-style muffler, offering a race-inspired aesthetic and a commanding presence on the road. It’s ideal for Subaru enthusiasts seeking enhanced throttle response and a customizable exhaust note for both daily driving and spirited track sessions.

Engineered with precision, the HKS Hi-Power exhaust utilizes high-quality SUH409 coated and SUS304 stainless steel materials for durability and corrosion resistance. The straight-through silencer design minimizes internal restrictions, significantly lowering exhaust back pressure compared to stock. This approach not only improves performance but also maintains a refined sound profile that can be tailored via the removable inner silencer. The adjustable tail tip adds a personal touch, allowing owners to fine-tune the exhaust’s visual stance.

For Subaru WRX and STI owners, this exhaust system enhances the driving experience by improving engine responsiveness and delivering a versatile sound that adapts to different driving environments. The substantial weight reduction from 22.4kg stock to 13.4kg further contributes to improved handling and agility. Whether navigating city streets or pushing limits on the track, the HKS Hi-Power Single Exit Cat Back offers a reliable and performance-oriented upgrade that complements Subaru’s sporty character.

Features & Specifications

This HKS Hi-Power Single Exit Cat Back exhaust is engineered for 2015-2021 Subaru WRX and WRX STI models and features an 85mm main pipe diameter with a single right-side exit. Constructed from coated SUH409 and SUS304 stainless steel, it delivers reduced exhaust back pressure and significant weight savings for Subaru enthusiasts seeking improved throttle response and customizable sound.

• Brand: HKS
• Product: Hi-Power Single Exit Cat Back 2015-2021 WRX / 2015-2021 STI
• Part Number: 31006-BF003
• Fitment: 2015-2021 Subaru WRX, 2015-2021 Subaru WRX STI
• Material: SUH409 (Coated) / SUS304 Stainless Steel
• Finish: Coated stainless steel
• Construction: Straight-through silencer design
• Origin: Japan
• Main Pipe Diameter: 85mm
• Tail Pipe Diameter: 119mm
• Exhaust Sound (with Inner Silencer): 82dB
• Exhaust Sound (without Inner Silencer): 96dB
• Minimum Ground Clearance: 115mm (Mid-pipe)
• Weight: 13.4kg (Stock: 22.4kg)

Key Benefits

• Performance: Reduced exhaust back pressure improves throttle response and unlocks engine potential for enhanced driving dynamics.
• Sound Control: Removable inner silencer allows drivers to tailor exhaust volume and tone for city driving or aggressive track use.
• Weight Savings: Significant reduction in system weight compared to stock improves vehicle agility and handling.
• Fitment: Designed specifically for 2015-2021 WRX and WRX STI models ensuring precise fit and easy installation.
• Aesthetics: Aggressive single-exit design with adjustable tail tip provides a race-inspired look and personalized style.
• Durability: High-quality coated SUH409 and SUS304 stainless steel construction ensures long-lasting corrosion resistance.

What's Included

• 1× HKS Hi-Power Single Exit Cat Back Exhaust System
• Removable inner silencer
• Adjustable tail tip
• Installation instructions