Active Autowerke S58 GESI Catted Downpipes - F97 X3M | F98 X4MBMW introduced a new valvetronic, single turbo version of its direct injection engine for the later F Chassis models beginning in 2016 and continues into the G Chassis models the evolution to the S58 engine continues with the twin turbo variant used in the M series vehicles. The Active Autowerke S58 downpipes for the X3M and X4M helps unleash some of the potential that is restricted by the OEM downpipes. Turbochargers are powered by spent exhaust