The BMW 4 Series GC 428i 245hp (F36 - 2014 - 2016) produces 245bhp and 350Nm in standard form. Our Stage 1 ECU tuning file raises output to 280bhp and 430Nm, a gain of 35bhp and 80Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.