Designed for the crowd that want a dose of additional grunt in their X4 M40i, Dinan delivers an exhaust system that offers improved tone and aggression over its stock counterpart. The first of the "pancake" style mufflers to make it to a BMW chassis, the X4 M40i created a unique engineering problem to solve and challenged the Dinan engineering team to produce additional volume and tone out of a much smaller and compressed can. After many permutations a tweaked helmholtz design was chosen that not only reduced resonance (or drone) at low RPM but also improved exhaust flow courtesy of reduced back pressure. Additionally, and most importantly, this design afforded the closest tonal change to that synonymous with a Dinan exhaust system -- a deep and smooth sporty sound that is civilized when you want it to be and pleasantly aggressive under hard acceleration.

Now available through Isringhausen BMW, the system is built to exacting specifications to ensure perfect fit using the factory hangers. It is made from 100% 16-gauge 304 stainless steel and will resist corrosion for years to come. The design features twin 89mm (3.5") laser engraved ceramic black or polished exhaust tips for a tasteful, high-performance look.

Benefits of the Dinan F26 X4 M40i Free Flow Exhaust:

+5 HP @ 6600 RPM, +4 FT-LB @ 6600 RPM
Twin 3.5" laser engraved polished exhaust tips
Easy bolt-on installation with included mounting hardware
Enjoyably louder, sportier sound
+ 100% 304 stainless steel construction

Part Numbers:

D660-0074: Dinan Free Flow Stainless Exhaust with Polished Tips for BMW F26 X4 M40i
D660-0074-BLK: Dinan Free Flow Stainless Exhaust with Black Tips for BMW F26 X4 M40i