The BMW 3 Series 340i 326hp (F3x LCI - 06 / 2015 - 2019) produces 326bhp and 450Nm in standard form. Our Stage 1 ECU tuning file raises output to 400bhp and 585Nm, a gain of 74bhp and 135Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.