The suggestion that Porsche is working on a new turbocharged 2.5-litre flat-four engine to power the Porsche Boxster and Cayman twins, first reported by Porsche fan site Flat-6 News, is in direct contradiction of statements made to CarAdvice by Porsche's engine development team leader Dr Martin Constein in February this year who said, "Turbo four-cylinder is not for Cayman. Cayman will always be six-cylinder."
Further to previous reports of the engine's development, and following the increasing trend towards powerful and efficient small capacity turbo-boosted engines, the new report claims sources inside the German sports car manufacturer have hinted at the new powerplant and suggested a combination of Porsche’s Direct Fuel Injection, VarioCam Plus variable valve timing system and a single turbocharger will see outputs of more than 260kW and 488Nm, and a redline of around 7500rpm.
An all-aluminium unit based on the 294kW/440Nm 3.8-litre flat-six that powers the current Porsche 911 Carrera S – but with two fewer cylinders – and tied to a version of the company’s PDK dual-clutch transmission, the engine will purportedly to debut sometime within the next 12 months. A traditional six-speed manual gearbox is still apparently under consideration.
The new turbocharged engine’s performance figures put it above the current 195kW/280Nm naturally aspirated 2.7-litre flat-six in the Boxster/Cayman and even the 232kW/360Nm 3.4-litre flat-six in the twin S models. The report also suggests the new engine could potentially find a home in Porsche’s much-discussed ‘Baby Boxster’, in a naturally aspirated state.
While engine sharing between Porsche and its now-owner Volkswagen is not uncommon – the 3.6-litre V6 and 3.0-litre turbo-diesel in the Porsche Cayenne are both Volkswagen Group items – the all-new turbo engine is thought to remain exclusive to Porsche.
Porsche has reportedly responded to the rumours, with an official source telling Autocar, it is still in an early development phase.
"On current planning, it will be another three years at least before we will be ready to reveal anything official on this subject," the source said.
"It is not due before 2016."