aFe Axle-Back Exhaust – BMW M3 / M4 (F80 / F82)

OVERVIEW

The aFe POWER MACH Force-Xp axle-back exhaust system replaces the rear section of the factory exhaust on the F80 M3 and F82/F83 M4 with a fully hand-built 304 stainless steel assembly. A free-flowing transverse muffler absorbs high-pitch tones to produce a deeper, more powerful note while unleashing the available horsepower and torque, and aFe reports maximum gains of +17 horsepower and +25 lbs. x ft. of torque.

The system incorporates a factory-style exhaust valve that reuses the car's original exhaust valve motor, so the factory valve behavior is retained — the valve opens, closes or partially obstructs the passage depending on throttle position for maximum performance. Construction is 2-1/2" to 3" mandrel-bent, brushed 304 stainless steel, 100% hand TIG-welded for corrosion resistance and strength that eliminates cracking. The muffler carries a high-temp powder-coated metallic black finish with a stamped aFe POWER logo.

All factory hanger and mounting locations are used, so installation is straightforward and fully reversible. All aFe exhaust systems are engineered and manufactured at aFe's Corona, California facility.

SPECS

• Maximum gains: +17 HP and +25 lbs. x ft. of torque
• Tubing: 2-1/2" to 3" mandrel-bent 304 stainless steel
• Construction: 100% hand TIG-welded, brushed 304 stainless steel finish
• Muffler: high-flow transverse design, high-temp powder-coated metallic black finish with stamped aFe POWER logo
• Tips: quad 3-1/2" diameter double-wall stainless steel with laser-etched aFe POWER logos
• Tip finishes available: polished, black or carbon fiber (see PART NUMBER)
• Exhaust valve: factory-style valve included; reuses the factory exhaust valve motor (motor not included)
• Mounting: uses all factory hanger locations, no cutting or modification required
• Emissions: this part does not require a CARB EO#
• Engineered and manufactured in Corona, California

PARTS INCLUDED

• Muffler assembly — 05-145182C (carbon fiber tips), 05-145182B (black tips) or 05-145803 (polished tips)
• Y-pipe — 05-145196
• 2-1/2" clamp sleeve — 05-41587
• 3" band clamp — 05-41055
• Fixing bow — 05-46273
• 12" nylon cable ties — 05-60167

TECH RESOURCES

Additional Parts Required

• None. aFe Power specifies no additional hardware for this part — the factory exhaust valve motor, hangers and mid-pipe are reused.
• Installer supplies: standard metric hand tools, penetrating oil, and a lift or jack and jack stands.
• Optional service items: stainless-safe metal polish for the polished tips, or a carbon-fiber-safe detailer for the carbon tip version.

Installation

• aFe Power 49-36338 MACH Force-Xp axle-back exhaust installation instructions (PDF)

PART NUMBER

• 49-36338-P — 304 stainless steel with polished tips
• 49-36338-B — 304 stainless steel with black tips
• 49-36338-1C — 304 stainless steel with carbon fiber tips

VEHICLE APPLICATIONS