Porsche 918 Spyder hybrid concept combines three electric motors with a 3.6-liter V8 to achieve 500 hp — and a jaw-dropping 78 mpg.
Lots of concept cars are like those gratuitous flings you had back in college: loads of initial excitement that rarely leads anywhere particularly meaningful. And when you meet again, you wonder what you ever saw in them.
The Porsche 918 Spyder, however, is different. Conceived as a successor to the company's exalted Carrera GT, the new two-seater points the way to an advanced performance flagship that, if company chairman Michael Macht has his way, will be ready to begin wooing customers in production guise within three years.
Revealed at the Geneva Motor Show, the 918 Spyder lays down a template for the future of the supercar in an age of heightened environmental awareness under Porsche's broad-based Intelligent Performance initiative. That initiative has spawned the wild 911 GT3 R hybrid race car.
In addition to a conventional gasoline engine, the dramatically styled 918 Spyder uses a trio of electric motors powered by a bank of lithium-ion batteries for four-wheel-drive propulsion as part of Porsche's first real foray into contemporary hybrid-drive systems.
With a 0-to-62-mph time of just 3.2 seconds, the new Porsche not only possesses straight-line performance matched by only a handful of conventionally powered supercars on sale today, but it also returns consumption of a combined 78 mpg on the European cycle, making most compacts appear thirsty.
Porsche's computer simulations suggest that the 918 Spyder will be able to lap the Nurburgring marginally faster than the Carrera GT, at 7.5 minutes.
Ask Macht what makes Porsche's latest concept so special, and he doesn't mince words: "It provides an emphatic answer to whether there can be high-performance supercars in the future. Many have said they are finished. This car shows they are not."
Created in six months after an official go-ahead last September, the 918 Spyder went from drawing board to concept car faster than any previous Porsche. Based around a lightweight carbon-fiber monocoque — to which engineers attached an intricate carbon-fiber engine cradle similar to that on the Carrera GT — the 918 Spyder's design also hints at the modern appearance we'll see on a whole new generation of Porsche models.
"We wanted to provide a glimpse of what our customers can expect in the future, not just on a supercar but other models in the lineup. There are a number of styling elements, in both the exterior and interior, that will be fully reflected on our road cars in the years to come," says design boss Michael Mauer.
At 177 inches long and just 43 inches tall, the 918 Spyder is five inches shorter and three inches lower but exactly the same width, 76 inches, as the Carrera GT. Its wheelbase of 104 inches is two inches shorter than Porsche's last limited-production road racer. Despite its apparent compactness, Porsche says its new car actually offers more space than the Carrera GT for its two occupants, an 18.5-gallon fuel tank behind the cabin and a luggage compartment up front in the nose.
The real attraction, however, is the advanced driveline. The gasoline-electric system includes a 90-degree, naturally aspirated, 3.6-liter V8 gasoline engine mounted behind the cabin in a classic midship layout. It is derived from the engine used to power the company's successful RS Spyder ALMS race cars but has been thoroughly redeveloped at Porsche's hallowed Weissach engineering center, with added capacity and various modifications aimed at providing greater durability.
Porsche isn't revealing a lot of details right now, but it does claim that the new engine can reliably rev to 9,200 rpm and is producing about 500 hp on the test bed, giving the 918 Spyder a specific output of 139 hp/liter. In a sign of things to come, the engine's efforts are supported by a trio of brushless electric motors that together are claimed to muster a further 218 hp.
Two motors sit within the front axle to provide individual drive to the front wheels. The third motor is mounted within the housing for the seven-speed dual-clutch gearbox, where it drives the rear wheels via an electronically controlled torque-vectoring clutch and a limited-slip differential.
Electrical energy for each motor is drawn from a bank of air-cooled lithium-ion batteries with overall capacity of 5.1 kilowatts per hour which sit low directly behind the seats for an optimal center of gravity. In pure electric mode, the range is about 16 miles. Recharging is via conventional means, but Porsche claims a high-amp system will provide a rapid two-hour fill-up.
Because of the differences in the operating programs for the gasoline engine and each electric motor, it's not just a simple process of adding the 918 Spyder's two horsepower figures together to arrive at a combined output. Porsche does claim a weight-to-power ratio of 4.8 pounds per hp. With claimed curb weight of 3,285 pounds, this points to a peak around 680 hp, 30 hp more than the Carrera GT's 5.0-liter V10.
Yes, the 918 Spyder is only a concept. But it is clearly destined to play a prominent role in Porsche's future road-car lineup. "There is no one inside Porsche who doesn't want to build this car," says Macht.
The version of the 918 Spyder we'll see in three years, running down the line at the Leipzig factory in Germany next to the Cayenne and the Panamera, hasn't been fully defined. Macht indicates it could follow the open-top layout of the concept car or gain a fixed roof to improve overall aerodynamics. "As soon as we start to receive feedback, we'll push on with the hard decisions," he says.
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