Our spy photographers in Northern Europe captured a very interesting prototype earlier today. A convoy of Bentley cars was caught testing with little camouflage and among the fleet was a black Flying Spur trial vehicle. Our spies told us every time the convoy parked, the drivers rushed to cover the car, which seemed a little suspicious. As it turned out, the car was out testing on public streets in winter conditions for a reason.

We’ve heard rumors about Bentley potentially working on a V8-powered plug-in hybrid version of its flagship sedan and this is most likely our first sighting of that vehicle. As you can see, there are some differences in the front fascia versus the existing Flying Spur V6 PHEV and the exhaust pipes are different as well. Most importantly, however, our photographers told us this prototype had a more sonorous engine and exhaust sound, which makes us believe there could be an eight-cylinder engine under the hood.

Gallery: Bentley Flying Spur V8 PHEV spy photos

Word on the street is Bentley will receive a version of Porsche’s electrified V8 with a plug that’s currently available in the Panamera Turbo S E-Hybrid sedan. It combines a twin-turbocharged 4.0-liter mill with an electric motor for a peak output of 690 horsepower (515 kilowatts) and 642 pound-feet (870 Newton-meters) of torque. If similar numbers are also available in the Flying Spur, this would make the new plug-in hybrid more powerful than the W12 version.

Speaking of the 12-cylinder engine, it’s currently only available in the Flying Spur Speed as the automaker discontinued the regular model with the thirsty powertrain. That engine makes 626 hp (467 kW) and 664 lb-ft (900 Nm) of torque and accelerates the big and heavy sedan from 0 to 60 miles per hour (0-96 kilometers per hour) in just 3.7 seconds. The top speed is around 207 mph (333 kph). We don’t expect the new PHEV model to beat those figures but it will deliver similar performance with the ability for zero-emissions driving and higher overall efficiency.

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