With the recent addition of the GranTurismo joining the Quattroporte in the Maserati lineup, the Italy-based automaker is enjoying a banner 2007. Sales are up almost 20 percent compared to the same period last year, and this year's entire GranTurismo production run has already been sold. To add a bit more sugar to its sweet success, the Quattroporte Sport GT S made its North American debut in Los Angeles.

While the Executive GT is geared more towards luxury, the Sport GT S is all about performance and fun.

The Sport GT S differentiates itself with a black-chrome mesh grille that provides a more aggressive look, dark-chrome 20-inch seven-spoke alloy wheels and quad exhaust pipes in black. Performance is enhanced with stiffer springs and dampers, and the car sits 10 mm lower at the front and 25 mm lower at the rear.

Power in all Quattroportes comes from a Ferrari-built 4.2-liter V8 engine that produces 400 horsepower. A new unique brake system developed in collaboration with Brembo gives this car major stopping power. In fact, the dual-cast discs consist of lighter material which allows for bigger front discs without adding weight.

Maserati’s luxurious interior features carbon fiber with aluminum threads, new front-seat designs that offer an advanced level of lateral support, and Alcantara leather for the seats, door panels and steering wheel.

Parked on the stand in L.A. next to the Quattroporte Sport GT S was the Pininfarina-designed GranTurismo. Suited for everyday use (according to Maserati), the high-performance sports car has a 405-horsepower 4.2-liter V8 engine producing 339 lb-ft of torque. Its concave grille sets the GranTurismo apart from just luxury to a genuine four-seat grand touring coupe.