The Alpina B5 B5 Bi-Turbo 540hp (F10/11 - 2010 - 2013) produces 540bhp and 730Nm in standard form. Our Stage 1 ECU tuning file raises output to 575bhp and 800Nm, a gain of 35bhp and 70Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.