The aFe MACH Force-XP 3" 304 stainless steel axle-back exhaust for 2008–2013 BMW 135i (E82/E88) with N54/N55 engines is a mandrel-bent system that improves flow and tunes exhaust pulses through a crossover balance tube. It is claimed to produce an estimated 11 hp and 10 lb-ft of torque. The system uses a free-flowing muffler, dual polished 3.5" tips, OE-style hangers and 304 stainless construction for a fuller yet controlled exhaust note and straightforward installation.
aFe MACH Force XP 08-13 BMW 135i L6-2.0L N54/N55 3in. 304 SS Axle-Back Exhaust w/Polished Tips