HKS Hi-Power Muffler Catback Single WRX (STI) 2015 - 2021

31006-BF003

Aggressive looks and sound, combined with low back pressure for greater tuning potential.

Features:
- Striking Presence - Featuring an 85mm pipe and a bullet-style muffler with a single right-side exit, it delivers an overwhelming presence and a distinctly race-inspired look.
- Volume control for every driving scene - The inner silencer can be attached or removed to control both volume and tone. Keep it moderate for city driving, or remove it for a more aggressive, sporty sound for the track.
- Adjustable tail tip - The adjustable tail tip allows you to adjust how far the tail extends, letting you achieve your ideal, personalized style.

Specifications:
- Shape of muffler: HP (Titan) (Hi-Power Muffler)
- Main material: S4, S3
- Diameter of tip: 119mm
- Diameter of center pipe: 74.7 > 85.0
- Close noise level: HKS 96dB *Note: Proximity exhaust noise measured according to California standards. Sound level recorded at 75% of maximum engine RPM.
- About road clearance(*2): Clearance: 115mm > Portion of the kit: Mid-pipe
- Product Weight: 18.4kg

Performance - Reduced Exhaust Back Pressure
- Featuring dramatically lower exhaust back pressure than the stock system, it improves exhaust flow for sharper throttle response and allows the engine to deliver its full performance potential.
Sound Pressure - Enjoy Sound Adapted to the Scene
- With the inner silencer installed, this exhaust delivers a subdued sporty tone. Removing it transforms the sound into a powerful, racing-inspired roar.
Tail Tip Adjustment - Adjustable Tail Tip
- The tail tip features a sliding adjustment mechanism, allowing you to customize the protrusion to your preference and enjoy a personalized look.
Layout Comparison - Aggressive Presence with Exceptionally Low Back Pressure
- By increasing the pipe diameter from the factory 60 mm to 85 mm, the system delivers a bold and commanding appearance. In addition, the straight-through silencer design eliminates internal restrictions, significantly reducing exhaust back pressure. The result is a noticeable improvement in driving performance and responsiveness.
Significant Weight Reduction
- Switching from a quad-exit to a single-exit and removing the mid-silencer results in a significant weight reduction, enhancing overall driving performance.