GM here in the U.S. has been drawing a lot of influence from its Australian arm, Holden, in the last few years. First, there was the Pontiac GTO, based on the Holden Monaro, and then the Pontiac G8, based on the Commodore. Of course, after the great financial meltdown, GM has stepped back from importing these Australian goodies to our shores, but that hasn’t slowed down the Aussies in any way.

Walkinshaw Performance, a company that tunes up Holdens into torque monsters, just lifted the veil on its latest creation, reports Carscoop. It is called the WP Series II Supercar, and it makes an insane amount of horsepower for a comfortable sedan, beating even the all-conquering CTS-V in that particular statistic.

Based on the Holden Commodore Series II, Walkinshaw Performance has enhanced this super sedan with an Edelbrock supercharger. Whereas the 6.0 liter V8 makes around 400 horsepower in stock guise, the supercharger boosts the engine to 617 horsepower and 575 ft-lbs of torque. All this power in a car that has near-perfect 50-50 weight distribution, four doors, and ample room for the whole family.

The suspension has also received a serious re-working, developed alongside Bilstein. Six-piston brake calipers provide stopping power to this monster sedan, and the interior has been touched up with some luxurious accouterments. Just 23 examples of this super sedan will be built, all painted Panorama Silver in honor of the original “Walky”, the Commodore SS Group A SV. With a sticker price of just under $100,000 (AUS, roughly $97k in US dollars), there are just a handful of people who can afford this super sedan anyways.