Valvetronic Design BMW F87 M2 Competition Equal Length Valved Sport Exhaust SystemWelcome to the Valvetronic Designs cat back exhaust system for the F87 M2C platform, or in other words, the solution to the S55 sound problem. For years enthusiasts have wanted to find a solution to the buzzy and raspy sound these cars produce from the factory. As the M2 Competition has the same problem as its big brother, we had to develop a solution for it. Our mission has been to find this hidden sound and allow all F87C owners to enjoy it. This