Among the many reasons that carmakers get involved in racing is the value of motorsports as a promotional tool.

It's considered a good way to burnish a brand's image, even if the cars being raced have little in common with the ones people can actually buy.

This week, Porsche provided a very entertaining example of how this can be done.

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It let loose one of its 919 Hybrid race cars in London traffic to promote the Panamera 4 E-Hybrid, a plug-in hybrid version of the recently-redesigned Panamera luxury sedan.

The 919 Hybrid is part of a class of purpose-built hybrid "prototype" cars that comprise the top performance class at the legendary 24 Hours of Le Mans endurance race—which it has won twice, including this year.

The stunt was intended to highlight technology transfer between Porsche's Le Mans race cars and its road cars.

Mark Webber driving a 2016 Porsche 919 Hybrid in London

Mark Webber driving a 2016 Porsche 919 Hybrid in London

For the London cruise, the 919 Hybrid was driven by Mark Webber, the ex-Formula 1 driver who now serves with the Porsche factory team.

With a Panamera following close behind, the 919 Hybrid hit the streets of London early in the morning.

But no streets were closed, so the race car mingled with regular traffic.

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Webber drove from Park Lane to the south bank of the River Thames, passing iconic London locations like Piccadilly Circus and Trafalgar Square.

It was admittedly a somewhat less strenuous drive than the endurance races the 919 Hybrid was designed for.

The 919 uses a 2.0-liter turbocharged V-4 engine to drive its rear wheels, with an electric motor powering the front wheels for short bursts—giving the car temporary all-wheel drive.

Mark Webber driving a 2016 Porsche 919 Hybrid in London

Mark Webber driving a 2016 Porsche 919 Hybrid in London

Regenerative braking and exhaust heat provide electricity, which is stored in an onboard lithium-ion battery pack.

The Panamera 4 E-Hybrid uses a 2.9-liter twin-turbocharged V-6 and a single electric motor, both of which are used to drive all four wheels.

While it's nowhere near as fast as the race car, the Panamera can at least drive solely on electric power for appreciable distances.

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Porsche claims an electric-only range of 31 miles, although that's as measured on the notoriously optimistic European driving cycle.

Aside from having the words "Porsche" and "Hybrid" in its name, the Panamera 4 E-Hybrid has virtually nothing in common with the 919 Hybrid.

But it's as close to that Le Mans-winning race car as most people will likely get.


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