HSV calls its 5.7-litre V8 engine the LS1 in an effort to differentiate it from Holden's less-powerful version, which is known as the Gen III - although they are the same base engine. The HSV unit benefits from a number of modifications to lift the standard engine's power and torque outputs from 225kW and 460Nm to 255kW at 5600rpm and 475Nm at 4000rpm. The modifications include a revised engine calibration for extra mid-range power and torque, ram air-type cold air intake, stainless steel exhaust extractors and a big bore dual exhaust system with high capacity, low back pressure catalytic converters and a low back pressure rear muffler.