Upon close examination, we can see that each side of the front bumper features a much larger grille than the normal Regal Sportback and TourX. The thick upper borders on the grilles also look like good places for some LED accent or fog lights. These larger grilles appear to be the only significant difference to the front, though. On the sides, there are slightly deeper side skirts than those on a standard Sportback, and the rear bumper looks to be lifted from the TourX, but without the wagon's aluminum cladding.
One other indication that this is a high-performance Regal is the car's front braking equipment. We can make out a Cadillac logo on the front brake calipers, which shows that this isn't running standard Regal stoppers.
As for what's under the hood, it's tough to say, but we don't think it will use a turbocharged four-cylinder as the previous generation did. Instead, we think it may be using a V6. That's a hard maybe. The base Regal's turbo four makes as much power as the old GS, and although Buick could crank up the boost for more power, it could also make use of the V6 it will offer overseas. In the mechanically identical Commodore, a 308-horsepower V6 will be available along with a 9-speed automatic and the same type of all-wheel-drive system as the Ford Focus RS. This option would make the upcoming GS more powerful than the old one, and the new standard model, plus offer all-wheel drive. We would like to see even more power than 308, since the top-dog previous-generation Insignia OPC had a 325-horsepower V6.