According to GM executives, the Opel Antara GTC (Gran Turismo Crossover) is the basis for the next-generation Saturn Vue. In concept form, this four-wheel-drive SUV offers only three doors and is powered by a 212-horsepower, twin turbo four-cylinder engine that GM suggests could propel the Antara to 60 mph in eight seconds. A production version would likely offer four doors and one or two fewer turbochargers.