The Mercedes SL 500 V8 BiTurbo 435hp (R231 - 2012 - 2015) produces 435bhp and 700Nm in standard form. Our Stage 1 ECU tuning file raises output to 550bhp and 850Nm, a gain of 115bhp and 150Nm, with no hardware modifications required. The file is delivered through the ByteFLASH portal and is ready to write to the vehicle.