Unveiled at the 2002 Sydney Motor Show, the HRT (Holden Racing Team) 427 was loosely based on the Holden Monaro bodyshell. The MacPherson strut front suspension was replaced by an aluminium double A-arm setup with adjustable dampers. A weight reduction program was enacted which included the fitment of a carbon fibre bonnet and magnesium wheels. A 7.0 litre (427ci) V8 from the Corvette C5-R was installed (coupled to a T-56 M12 six-speed transmission), hence the name.
Originally intended to be put into production as competition against vehicles such as the Porsche 911 GT2, the idea was abandoned due to an unworkable business case based on the original production targets. It was to be the quickest ever (up to that time) HSV with a reported top speed of 299 km/h (186 mph). Only two street specification cars were ever built (although four racing versions were built by Garry Rogers Motorsport for use in the short-lived Bathurst 24 Hour race and Australian Nations Cup Championship). The road going cars had a reported 420 kW / 571 PS; 563 hp) of power and 780 N·m (580 lb·ft) of torque. The engines for the HRT 427 were built by Melbourne based John Sidney Racing, best known for their long time success in Australian Sprintcar and NASCAR racing
Source: Wikipedia (original)