The BMW 4 Series GC 435i PP 339hp (F36 - 2014 - 2016) produces 339bhp and 450Nm in standard form. Our Stage 1 ECU tuning file raises output to 365bhp and 520Nm, a gain of 26bhp and 70Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.