We saw the Pontiac G8 GXP at the 2008 New York Auto Show earlier this year. The most powerful car in the GXP series, GM claims that the 6.2L V8 small-block under the hood produces 402-hp and 402 lb-ft of torque. That allows for a 0-60 mph time of 4.7 seconds.

Well after some dyno testing, engineers have found more power under the hood. After undergoing testing on a SAE J1349 dyno, GM found that the 2009 Pontiac G8 GXP produces a total of 415-hp with a maximum torque of 415 lb-ft. Not sure if that effects the 0-60 time by much. The engine is mated to a Hydra-Matic 6-speed automatic with an optional 6-speed Tremec TR6060 manual.

The 2009 Pontiac G8 GXP will hit dealerships later this year. Pricing will be announced closer to launch.

2009 Pontiac G8 GXP:

Source: GM Inside News