The Holden Special Vehicles (HSV) GTS and Maloo GTS are now available with an upgrade boost developed by Walkinshaw Performance. The W507 package was created primarily for those who are not satisfied with the stock output provided by the cars and are willing to spend $7,990 AUD to receive a custom cold air intake, ceramic coated headers, a cat back exhaust system as well as an upgraded pulley. Also included in the kit are special decals, an optimized ECU and you also get a certificate of authenticity.
After all these changes are implemented, the V8 6.2-liter supercharged engine in the HSV GTS and HSV Maloo GTS unleashes no less than 680 bhp and a peak torque of 850 Nm (626 lb-ft) which should be more than enough for even those who have a great thirst for power.
Source: Walkinshaw Performance