Berlin, Germany – Porsche has halted deliveries of its new 911 GT3 after two of them caught fire recently. Engineers at Porsche’s Stuttgart-based headquarters are examining the remains of the gutted vehicles, used in Switzerland and Italy, to determine the cause of the fires. Porsche expects to conclude the investigation this week, a spokesman said, adding that the company had already delivered 322 of the GT3 models this year. Porsche has yet to announce whether those cars will be recalled. The latest GT3 is a track-focused machine, powered by highly modified normally aspirated 3.8-litre flat six that revs to 9000rpm and pushes outputs of 350kW and 440Nm. According to Porsche, the GT3 takes just 3.5 seconds to get to 100km/h, tops out at 315.3km/h and laps the Nürburgring-Nordschleife in less than 7m30s.