The G8 GXP will have a 6.2-liter LS3 V-8 (the G8 GT uses a 361-bhp 6.0-liter) is pretty much the same terrific new pushrod small-block found in the 2008 C6 Corvette — one of the very best V-8s ever made. Although horsepower and torque numbers aren't finalized yet, Pontiac estimates the outputs at 402 bhp and 402 lb.-ft. of torque (the torque for the 6-speed manual is estimated at 400 lb.-ft.). The horsepower figure is down 28 to the Vette, but torque is about the same.......
.....Pontiac estimates the G8 GXP will hit 60 mph in just 4.7 seconds and will run the quarter mile in 13 flat.