Porsche 718 Boxster Spyder to get flat-six

Porsche is secretly developing a 718 Boxster Spyder which jettisons the core model's turbocharged flat-four-cylinder engine for a naturally-aspirated 4.0-litre flat-six from the latest 911 GT3.

According to British magazine Autocar Porsche's plan for the six-cylinder model is simple: to be the "most involving Boxster" so far.

While confirming the GT3 engine was destined for the Boxster Spyder, earlier in the year, Porsche's head of GT car development, Andreas Preuninger, told the magazine "natural aspiration is one of our main USPs".

It's thought to help distance the new model from the flagship 911 GT3, the Boxster Spyder won't pack the full 368kW/460Nm engine specification as installed in the track-biased 911.

Created for purists, the Spyder will come with a six-speed manual gearbox as standard, although Autocar suggests a seven-speed PDK dual-clutch transmission will also be offered as an option.

As well as the heroic flat-six, which can rev to 9000rpm in its 911 GT3 application, to reduce weight and boost performance, the Boxster Spyder will ditch sound deadening material, its electric roof, and air conditioning.

It's thought, once the Boxster Spyder is launched in early 2018 a Cayman GT4 will also be offered with the same 4.0-litre flat-six 911 GT3 engine.