Dinan Free Flow Axle-Back Exhaust for 2020-24 X3 M, 2020-25 X4 M - D660-0086-BLK

Give your BMW X3M or X4M a deeper, louder exhaust note and more aggressive quad-tip appearance with the Dinan D660-0086-BLK Free Flow Axle-Back Exhaust. Designed for select 2020-2025 BMW F97 X3M and F98 X4M applications, this performance exhaust is constructed from TIG-welded T304 stainless steel and features larger 76mm piping, retained computer-controlled exhaust valves, and four 4.5-inch black ceramic coated exhaust tips. Dinan reports maximum gains of 8 HP and 6 lb-ft of torque at 6,600 RPM while reducing system weight by approximately 5 pounds compared with stock.

The Dinan Free Flow system increases pipe diameter from the factory 70mm to 76mm for improved exhaust flow. When the valves open under high-load conditions, exhaust is directed through the freer-flowing outer paths for a deeper, fuller, more aggressive tone. With the valves closed, gases are routed through the muffler and exit the inner tips for quieter operation. Internal drone-abatement technology helps control unwanted cabin resonance regardless of valve position.

Four 114mm (4.5-inch) double-wall tips fill the factory rear valance openings and feature Dinan's straight-cut design, laser-engraved branding, and black ceramic coating. Dinan's inverted-clamp “Tuck-it” tip design helps conceal the clamps for a cleaner installed appearance.

Key Features & Specs:

• Brand: Dinan
• Series: Free Flow
• Product Type: Axle-Back Exhaust
• Part Number: D660-0086-BLK
• Fitment: BMW X3M / X4M
• Chassis: F97 / F98
• Material: T304 Stainless Steel
• Body Material: T304 Stainless Steel
• Pipe Material: T304 Stainless Steel
• Construction: TIG-Welded
• System Finish: Brushed
• Tip Finish: Black Ceramic Coated
• Exhaust Tip Quantity: 4
• Tip Diameter: 4.5 in / 114mm
• Tip Style: Straight-Cut, Double-Walled, Clamp-On
• Tip Design: Inverted-clamp “Tuck-it” design
• Tip Branding: Laser-Engraved Dinan Logo
• Pipe Diameter: 76mm vs. 70mm stock
• Maximum HP Gain: +8 HP at 6,600 RPM
• Maximum Torque Gain: +6 lb-ft at 6,600 RPM
• Weight Reduction: Approximately 5 lb lighter than stock
• Exhaust Valves: Twin 76mm computer-controlled valves
• Valve Restriction: Dinan states the 76mm valves are 30% less restrictive than OE valves
• Valve Operation: Retained for quieter low-speed driving and increased flow under high-load conditions
• Sound: Louder, deeper, sportier exhaust tone
• Drone Control: Drone-abatement technology designed to reduce cabin resonance
• Installation: Bolt-on
• Mounting Hardware: Included
• Clamps Included: Yes
• Hangers Included: Yes
• Labor Time: 2.5 hours
• Length: 54 in
• Width: 29 in
• Height: 10 in
• Weight: 72 lb
• Grade Type: Performance
• Dinan Point Value: 3
• Emission Code: 5
• UPC: 813725029252

Fitment:

• 2020-2024 BMW X3 M - F97
• 2020-2022 BMW X3 M Competition - F97
• 2020-2025 BMW X4 M - F98
• 2020-2022 BMW X4 M Competition - F98