Why F90 Downpipes Are a Must for Your M5
If you're looking for the single best way to wake up that S63 engine, swapping out those restrictive stock units for some high-flow f90 downpipes is probably the first thing you should do. The BMW M5 is a masterpiece right off the showroom floor, but let's be honest—BMW had to play by the rules. They had to meet noise regulations, emission standards, and keep the car refined enough for someone who just wants a fast daily driver. But if you're the type of person who wants to hear the turbos whistle and feel the full weight of that twin-turbo V8, those factory catalytic converters have to go. ...