Dinan Free Flow Axle-Back Exhaust – BMW M235i (F22)

OVERVIEW

Dinan engineered this axle-back exhaust for the F22 M235i to improve exhaust flow by reducing back pressure, which increases power output and gives the car a sportier voice that stays civilized when you want it to be and turns pleasantly aggressive under hard acceleration. A Helmholtz chamber built into the design cancels resonance so low-RPM drone does not intrude on the cabin.

The system is built to exacting specifications for a perfect fit on the factory hangers and is made from 100% 16-gauge 304 stainless steel, so it will resist corrosion for years. It finishes with twin 89 mm exhaust tips in polished stainless or ceramic black for a tasteful, high-performance look.

SPECS

• Maximum gain: +6 HP @ 6600 RPM and +5 lb-ft @ 6600 RPM
• 100% 16-gauge 304 stainless steel construction
• Twin 89 mm (3.5 in) laser-engraved exhaust tips, polished stainless or ceramic black
• Helmholtz chamber to reduce low-RPM drone
• Mounts using the factory brackets and hangers for factory-like fitment
• Shipping dimensions: 50 in L x 34 in W x 12 in H
• Weight: 47 lb
• Dinan labor time: 1.3 hours
• Emissions status per Dinan: 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 limited warranty: the remainder of the BMW new-car limited warranty, up to 4 years / 50,000 miles, if the vehicle is still covered by the factory warranty; otherwise 2 years / unlimited mileage. Wear items are excluded.

PARTS INCLUDED

• Complete axle-back exhaust kit as supplied by Dinan, including the tube clamp used during installation; see the installation instructions for the full bill of materials.

TECH RESOURCES

Additional Parts Required

• None. Dinan specifies no additional hardware for this part; the required tube clamp is supplied in the kit.

Installation

• Dinan Free Flow Axle-Back Exhaust Installation Instructions (INS660-0047, Rev. 07/31/14) - PDF
• Dinan labor time: 1.3 hours

Notes

• Dinan states this part is not compatible with vehicles equipped with the M Performance rear valance; Dinan supplies a separate part number (D660-0048) for those cars.

PART NUMBER

• D660-0047-BLK - ceramic black tips

VEHICLE APPLICATIONS