Invidia Q300 Cat Back Exhaust Stainless Tip Honda Civic Si Sedan 2006-2011 | HS06HC4G3S

The Invidia Q300 Stainless Steel Tip Cat-Back Exhaust for the 2006–2011 Honda Civic Si Sedan is engineered for drivers who want a refined, daily-friendly exhaust tone with improved flow and premium build quality. Featuring Invidia’s signature Q300 muffler design and a polished stainless steel tip, this system delivers a deep, smooth exhaust note without excessive noise or cabin drone.

This is one of the most popular choices among Civic Si owners who want an upgrade that stays comfortable for daily driving while still offering a noticeably more refined and performance-oriented sound under acceleration.

Key Features & Benefits

• Polished stainless steel exhaust tip for clean OEM+ styling
• Large-volume Q300 muffler for deep, refined tone
• 70mm mandrel-bent stainless steel piping for improved exhaust flow
• Low cabin drone for comfortable highway driving
• TIG-welded SUS304 stainless steel construction for durability
• Direct bolt-on fitment using factory mounting points
• Balanced performance and street drivability

Performance Characteristics

• Sound Level: Mild to moderate
• Tone: Deep, smooth, and non-raspy
• Drone: Very low compared to aggressive exhaust systems
• Performance: Mild gains in throttle response and flow efficiency

Community feedback consistently describes the Q300 as one of the best daily-driven exhaust systems for the 8th gen Civic Si due to its refined tone and lack of drone, especially on long drives. 

Installation Notes

• Direct bolt-on cat-back system
• Uses factory hanger locations
• Professional installation recommended
• Exhaust gasket replacement recommended during install
• No cutting or welding required