The G8 is Pontiac's new full-size sedan; under the skin it's a clone of the Holden Commodore, a product of GM's Australian division. Pontiac introduced the G8 with a 361 horsepower V8 as the top-of-the-line engine. For 2009, that will be supplemented by what you see here: The G8 GXP, with a 402 hp 6.2 liter Corvette engine under the hood. Man, those Australians know how to party.