Porsche 918 Spyder exclusive

When Porsche first showed us its 918 Spyder concept two years ago, we all struggled to believe what we were being told. Here was a new 200mph supercar which would lap the fearsome Nurburgring in less than seven minutes, 22 seconds, yet could average 94mpg and emit a mere 70g/km. Not only would it be the cleanest petrol- engined plug-in hybrid in the world, it would also be one of the fastest supercars ever created.

Too good to be true? To find out, we visited a Porsche test facility in southern Italy to spend a day with the team tasked with turning the concept into a reality.

It’s immediately clear that significant alterations have been made since the 918 was revealed. For starters, there’s been a complete rethink on the electric motors acting on the front wheels. Instead of two, there’s now a single 80kW motor powering both wheels via a single-speed transfer gearbox.

Another electric motor (rated at 90kW) is sandwiched between the mid-mounted V8 and the seven-speed PDK gearbox (taken from the 911 Turbo then turned 180 degrees and flipped upside down). This spins at the same speed as the engine and doubles as a starter motor, too.

The mid-mounted 570hp 4.6-litre V8 – based on the 3.4-litre in the Porsche RS Spyder LMP2 race car – has direct fuel injection, dry sump lubrication, variable timing for both intake and exhaust cams, a very high compression ratio and a 9,000rpm rev limit.

The exhaust has been redesigned, with gases now exiting via two new ‘top-pipes’ pointing upwards just behind the cockpit. Engineers discovered having two exhaust manifolds hanging off the V8 engine risked cooking the lithium-ion battery.

In total, there are three power units managed by no less than 55 ECUs. Power is a can of worms as you can’t simply add the three power figures together. The front motor is single geared anyway (and becomes redundant beyond 235km/h, or 146mph), so that needs taking into account. But Porsche says that in third gear, peak torque of 880Nm is available at 2,000rpm. That’s a monster amount in anyone’s language.