Dinan D660-0085-BLK Free Flow Axle-Back Exhaust — BMW G20 M340i & G22/G23/G26 M440i
Regular price
$2,399.95
Dinan’s valved T304 stainless-steel axle-back exhaust for supported BMW M340i and M440i models, finished with four ceramic-black 102 mm tips.
Confirmed chassis coverage
- BMW G20 M340i
- BMW G22 M440i Coupe
- BMW G23 M440i Convertible
- BMW G26 M440i Gran Coupe
Confirm model year, chassis, drivetrain, production date, rear valance, and factory exhaust configuration against Dinan’s current application data before ordering.
Performance and sound
- Larger 76 mm tubing compared with the original 70 mm system
- Dinan reports gains of up to 6 horsepower and 5 pound-feet of torque on its test vehicle
- Approximately four pounds lighter than the original system
- Twin 76 mm exhaust valves retain computer-controlled quiet and high-load sound behavior
- Four straight-cut, double-wall, ceramic-black tips with laser-engraved Dinan branding
Construction
- TIG-welded brushed T304 stainless steel
- Application-specific hangers, clamps, valves, and mounting hardware
- Bolt-on axle-back layout designed around the factory rear valance
Installation
Professional installation is recommended. The original valve actuator is reused and the supplied second valve and actuator are installed on the opposing side. Verify valve operation, clearances, alignment, clamp torque, and tip position after the first complete heat cycle.
Emissions and warranty
Dinan assigns this product Emission Code 5, meaning it does not affect vehicle emissions and is not covered by emissions regulations. Warranty eligibility, exclusions, and claim handling are governed by Dinan’s current written warranty terms.