Dinan - Free Flow Axle-Back Exhaust - 2017-2020 BMW 440i - D660-0077

Dinan engineers designed the F33/F36 440i exhaust to improve exhaust flow by reducing back pressure, resulting in increased power output and a great sporty sound that is civilized when you want it to be, and pleasantly aggressive under hard acceleration. Not only is the tone improved but the additional burbles and pops that come with it are simply intoxicating. Dinan also incorporates a Helmholtz chamber design that reduces resonance or"drone" at low RPM.

The system is built to exacting specifications to ensure perfect fit using the factory hangers. It is made from 100% 16 gauge 304 stainless steel and will resist corrosion for years to come. The design features twin 89mm (3.5") polished or cermic black exhaust tips for a tasteful high-performance look.

Factory computer controlled exhaust valve is eliminated.

Features

• More Power: + 6 HP @ 6600 RPM, + 5 LB-FT @ 6600 RPM
• Helmholtz chamber to reduce drone
• Enjoyably louder, sportier sound
• Twin 89mm (3.5") laser engraved, polished or ceramic black exhaust tips
• 100% 304 stainless steel construction
• Uses the factory brackets and hangers for a factory-like fitment

Specifications

This part is legal for sale or use on Emissions Controlled Vehicles, Uncontrolled (Non-Emissions Controlled) Vehicles, and Racing Use Only Vehicles because it does not affect vehicle emissions and is not covered by emissions regulations.

Installation Instructions:

• Installation Instructions (PDF)