OVERVIEW
Dinan engineered the F33/F36 440i axle-back exhaust to improve flow by reducing back pressure, which increases power output and produces a sporty tone that stays civilized at cruise and turns pleasantly aggressive under hard acceleration, complete with burbles and pops on overrun. A Helmholtz chamber is built into the design to reduce low-RPM resonance and drone.
The system is built to exacting specifications and mounts using the factory hangers and brackets for a factory-like fit. It is made from 100% 16-gauge 304 stainless steel for long-term corrosion resistance, and finished with twin 89mm (3.5 in.) laser engraved tips available in polished stainless or black ceramic coating. The factory computer-controlled exhaust valve is eliminated with this system.
SPECS
- Maximum gain of +6 HP @ 6600 RPM (Dinan measured)
- Maximum gain of +5 lb-ft of torque @ 6600 RPM (Dinan measured)
- 100% 16-gauge 304 stainless steel construction
- Twin 89mm (3.5 in.) laser engraved tips in polished stainless or black ceramic coating
- Helmholtz chamber design to reduce low-RPM drone
- Uses the factory brackets and hangers for factory-like fitment
- Factory computer-controlled exhaust valve is eliminated
- Dinan published installation time: 1.2 hours
- Emissions status per Dinan: "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."
- Dinan warranty: the remainder of the BMW new-car limited warranty (up to 4 years / 50,000 miles) or 2 years / unlimited mileage from purchase, whichever is greater; wear items, maintenance parts, improper installation and competition use are excluded
PARTS INCLUDED
- Dinan high performance muffler assembly with twin 89mm tips
- Muffler hangers, rubber hangers, clamping bushings, lock nuts and washers as called out in the installation instructions
- Complete kit as supplied by Dinan; see the installation instructions for the full bill of materials
TECH RESOURCES
Additional Parts Required
- None. Dinan specifies no additional hardware for this part.
- Installer-supplied tools only. Dinan notes some mechanical skill is required and recommends a qualified BMW facility if you are unfamiliar with the procedure.
Installation
Notes
- Fitment should be confirmed with Speed Logic before ordering.
PART NUMBER
- D660-0077 – polished, laser engraved stainless tips
- D660-0077-BLK – black ceramic coated tips
VEHICLE APPLICATIONS
| Make | Model | Chassis | Engine | Years |
|---|---|---|---|---|
| BMW | 440i | F32 / F33 / F36 | B58 3.0L Turbo I6 | 2017–2018 |
| BMW | 440i xDrive | F32 / F33 / F36 | B58 3.0L Turbo I6 | 2017–2018 |