Increasingly strict European emissions regulations will likely spell the end of the Porsche 911 GT3's current naturally aspirated 4.0-liter flat-six. Porsche GT boss Andreas Preuninger said the engine could survive for some time under U.S. emissions regulations, but it likely only has a few years left in Europe. While Preuninger didn't confirm that the next-gen GT3 engine will be turbocharged, he suggested that it might be the solution.