Dinan D660-0085-BLK Free Flow Axle-Back Exhaust System for BMW - M340i/M440i

The Dinan Free Flow Axle-Back Exhaust transforms your 2020-2024 BMW M340i or M440i with enhanced performance and an aggressive exhaust note. Engineered with precision, this exhaust system delivers measurable power gains while reducing weight and maintaining the factory exhaust valve functionality for refined daily driving.

Performance Gains:

• Power increase of 6 HP at 6600 RPM and 5 lb-ft of torque at 6600 RPM
• Larger 76mm diameter piping compared to the restrictive 70mm stock system for improved exhaust flow
• Twin 76mm exhaust valves are 30% less restrictive than OE valves
• 4 lbs lighter than the factory exhaust system

Premium Construction:

• 100% 304 stainless steel construction for durability and corrosion resistance
• Quad 4-inch diameter double-walled exhaust tips with ceramic black finish and laser engraving
• Clamp-on tip design for easy installation and removal

Smart Exhaust Valve Technology:

• Retains computer-controlled exhaust valves for versatile sound management
• Valves limit noise during low-speed driving and cruising conditions
• Valves open fully during high-load acceleration for maximum flow and an exhilarating sound
• Reuses stock valve actuator and adds a second valve/actuator to the opposing side for balanced flow

Installation:

• Direct bolt-on installation with no modifications required
• All necessary mounting hardware included
• Designed as a complete axle-back replacement system

This Dinan axle-back exhaust delivers the perfect balance of performance, sound, and sophistication for enthusiasts who demand more from their BMW without sacrificing daily drivability.