Porsche boss Matthias Müller has confirmed long-running rumours suggesting future incarnations of the Boxster and Cayman are in line to receive a turbocharged four-cylinder boxer engine.

In an interview with Germany’s Auto Motor und Sport magazine, 60-year-old Müller said Porsche road cars would follow the lead of the company’s hi-tech 919 Hybrid race car in receiving four-cylinder engines.

But while the 919 Hybrid runs a unique vee-configured engine, the unit being readied for the Boxster and Cayman will follow the lead of Porsche’s classic six-cylinder engine with a 180deg horizontally opposed layout as part of a modular engine strategy.

“We will continue with the downsizing strategy and develop a new four-cylinder boxer engine which will see service in the next-generation Boxster and Cayman,” said Müller. “We will not separate ourselves from efforts to reduce CO2.”

When queried on the output of the new four-cylinder boxer engine, Müller suggested it would boast “up to 400ps [395bhp]”.

Today’s naturally aspirated 3.4-litre six-cylinder engine develop up to 325bhp and 335bhp respectively in the new range-topping Boxster and Cayman GTS models, which were revealed earlier this week.