VRSF Race Downpipes BMW 550i 650i 750Li N63 Slip Fit 08-17VRSF Race Downpipes BMW 550i 650i 750Li N63 Slip Fit (2008 2017) The N63 V8 twin turbo is a big engine with big potential, and the factory downpipes are holding it back. The VRSF Race Downpipes eliminate that restriction with a smooth mandrel bent SS304 design that reduces back pressure, delivers 50 55 horsepower and 60 65 torque gains at the wheels when tuned, and gives the N63 an exhaust note worthy of the V8 badge. Unlike competitors who neck down