Horsepower ratings from the first pic are at the hubs, not the wheel or tranny.

http://www.motorauthority.com/news/s...hp-at-the-hubs

"A few days ago we were talking about Nissan wanting to get the GT-R to an SAE-certified 480hp so it would match the Porsche 911 Turbo, one of its chief rivals. It looks like that should be an easy feat if the dyno numbers coming out of Japan today are solid - and it looks like they are. According to testing done on a Dynapack dynamometer, the new GT-R pumps 482PS (475hp) to all four hubs, with torque peaking at 580Nm (428lb-ft) at the hubs.

Assuming parasitic drivetrain losses around 15% - although the loss could be even larger given the GT-R’s all-wheel drive platform - that would put power at the crank around 550hp and 495lb-ft of torque - absolutely insane numbers for a 3.8L engine, twin-turbo or not. Suspicious? Head on over to NAGTROC, the North American GT-R Owners Club forums, where poster Chuck H has links to photographic evidence of the testing, complete with shots of the dyno screen.
While these numbers seem to fit more aptly with the GT-R’s 3800lb curb weight and its scorching ‘Ring times, it still seems odd that a car with a drag coefficient of 0.27 would top out at anything under 200mph with 550hp under the hood. Maybe there’s more to this story than meets the eye. We’ll keep you updated as things unfold."-Motor Authority

 

Well, that explains some of the performance numbers

 

I like how Nissan appears to be underrating it's own product!

It makes it then all the more shocking when independent tests discover that the car is more powerful and performs beyond Nissan press released specs. Very clever of them. And smart. They're doing this whole thing right. I'm amazed.