Porsche 918 Spyder: The Shape of Supercars to Come

Driving down the pit lane of Porsche's test track outside the company's Leipzig, Germany, factory, 918 Spyder prototype No. 25 is nearly silent as its runs on electric power. Exiting onto the track, the faint whine of the electric motors grows louder as we approach 94 miles per hour, the electric-mode limit. Finally, the midmounted 4.6-liter V-8 engine roars to life, the exhaust pipes booming inches behind my head.

The 918 Spyder is Porsche's next supercar, following in the footsteps of the Carrera GT, the 911 GT1, and the 959. It's an 887-hp plug-in electric hybrid that proves performance and efficiency are not mutually exclusive. As project leader Frank-Steffan Walliser explains: "For the first time, the technical solutions support both lap time and fuel consumption."

After several laps behind the wheel and a full day investigating what makes it work, we're convinced that the 918 points the way to a bright future for sports cars despite ever-tightening fuel-economy and emissions standards. And while this $845,000 car is out of reach even for rich people, the lessons learned will make their way down to more affordable rides.

As we first noted in our ride-along at the Nürburging last year, the 918 Spyder is powered by a midmounted V-8 engine and two electric motors. Now, as the Sept. 9, 2013, production start date grows near, Porsche has newer power figures. The front motor is good for 127 hp and the rear makes 154. By itself, the 918's electric output is more than the original 911 Turbo. Add in the 608-hp gas engine and the 918 Spyder cranks out a peak 887 hp.

The 4.6-liter V-8 is adapted from Porsche's RS Spyder race car. It revs to 9150 rpm and features titanium connecting rods, a carbon-fiber airbox, and an oil channel that runs inside the crankshaft to keep the connecting rod bearings cool. The exhaust exits not in the rear but on top, right behind the cabin.

Air-cooled fans rejoice! While Porsche shifted to liquid cooling for its engines years ago, the rear motor, which sits between the engine and the seven-speed dual-clutch gearbox, is chilled by both air and water. A built-in fan attached to the outside rotor flows cool air around the coils, while a coolant channel in the stator keeps the center of the motor cool. This allows for better power density: The rear motor is 27 hp stronger than the front unit but is about the same size. Expect to see this next-generation motor on other Porsche hybrids before long.

The lithium-ion battery pack sits right behind the seats, mounted at the bottom of the car to lower the center of gravity. While the 312 cells that make up the unit look the same as the ones in the Panamera Hybrid, the 918's cells have tighter internal windings of the anode and cathode. This setup is more expensive but also allows for higher energy capacity and faster charging and discharge. The batteries are cooled with an independent coolant circuit that taps into the air conditioning when extra chilling is required. Total capacity is 5.8 kilowatt-hours. Charging takes about 7 hours on 110-volt power or less than two hours on 220-volt power. With a DC fast-charging connection, the 918 Spyder can take an 80 percent charge in half an hour. Electric-only range is about 18 miles.

Possibly the biggest innovation in the 918 Spyder is its brakes. Most hybrids have an unnatural pedal feel that comes from combining regenerative power with conventional friction brakes. The 918 solves this problem with what Porsche calls an Active Volume Reservoir in the brake system. When the driver pushes the brake pedal, the electric motors provide the braking up to 0.5 g'she's talking about g-forces in braking, right? We use "g's", even for amounts less than 1 g's (typical hybrid systems are limited to 0.2 g's). When that happens, the active reservoir removes hydraulic pressure from the brake lines in an amount equivalent to the braking force from the electric motors. When the carbon-ceramic brakes finally need to be used, the seamless blending of the two systems results in a constant and consistent pedal feel. At least in theory. We still noticed some uneven pressure in the prototype, but even in preproduction form it was better than any hybrid or EV we've driven.

Steering assistance in the 918 is electric, a necessity since it needs to work when the engine is off. But the rear wheels steer as well, up to 3 degrees in each direction. At low speeds the back axle turns opposite of the front wheels, shrinking the turning radius. Above 31 miles per hour, the rear wheels turn in the same direction as the front, improving stability. This feature has already trickled down to the upcoming 911 GT3 and Turbo.

The 918's complementary mission of performance and efficiency is perfectly illustrated in the active aerodynamics. Shutters on the front grille close in EV mode, which reduces drag. At higher speeds the rear wing extends to provide more downforce. To balance the change in aerodynamics, channels in the underbody diffuser open up to increase front downforce as well.

Compared to the Carrera GT, the 3715-pound 918 Spyder is about 330 pounds heavier. But that includes more than 660 pounds of hybrid components, meaning Porsche as meant, can?saved weight everywhere else. Even the carbon-fiber chassis, which is already light, uses carbon-fiber inserts for mounting and joining points (traditional carbon-fiber construction uses heavier aluminum). The LED headlights weigh just 1.9 pounds (and you can already get them on a Carrera). Our favorite piece of trivia is that the steel that covers the top of the exhaust has 10,346 weight-saving, laser-drilled holes.

The Weissach Package, available for a cool $84,000, takes weight savings even further, with cloth seats, Alcantara interior trim (instead of heavier leather), magnesium wheels, carbon-fiber rear antiroll bar, and ceramic wheel bearings. The air conditioning is also excluded, but saves only 2.2 pounds because the system is still used for battery components. Both the AC and the deleted stereo can be added back on at no charge.

The 918 Spyder previews the future direction for Porsche interiors. The concept behind the design is to keep driver information separate from infotainment. The center-mounted tachometer, a Porsche hallmark, also incorporates the electric power and regeneration into the dial. A multifunction display in the right dial shows only trip information and vehicle status. Radio and navigation are shown on the upper information screen or on the center console.

The center console itself is one of the best touchscreen systems I've encountered. The menus follow an intuitive structure and the response time on the demonstration unit is excellent. What's special about this system is how you can reconfigure certain screens to show whatever information you prefer. Anything from the trip computer, entertainment, or navigation can be dragged and dropped onto the customizable screen in the setup mode.

There are five driving modes in the 918, all controlled by a dial on the steering wheel. I had a chance to sample all of them on Porsche's track. The first, E-Power, keeps the engine powered off until the batteries drop below 20 percent, speed exceeds 94 mph, or you floor the throttle. Hybrid mode runs with a focus on fuel efficiency and keeping the engine off as much as possible. The upside of this is that you get to hear the engine fire up over and over as you drive. And even in such an economy setting, it's nearly impossible to ignore all the power from engine and electric motors.

One step further, into Sport mode, keeps the engine running all the time, and this is where the 918 starts to drive like a true supercar. The exhaust note wails, activating a short circuit directly to the pleasure center of the brain. After two laps it's hard to believe the 918 Spyder has more to offer, but Race mode increases everything even further. The throttle response is sharper, the engine revs higher before shifting, and the electronics are set for maximum energy recuperation for the batteries, which allows for more electric assist coming out of the turns.

If you push the red button on the center of the selector dial it activates the hot-lap function, which is an all-out, screw-the-battery-does he mean charge as in battery charge ( or as in "charge ahead!"), if battery charge, there should be a hyphen here to: screw-the-battery-charge modecharge mode aimed at the hottest single-lap times.

What's most incredible about the 918 Spyder is that for all the electronics that manage hundreds of parameters among the motors, engine, brakes, and aerodynamics, none of that complexity is apparent from behind the wheel. It's completely transparent. I couldn't tell exactly how much power the front axle motor was using, I only knew that the 918 screams out of corners without losing any traction. It's remarkable easy to drive, yet still thrilling. Some of that thrill comes from the low seating position and the blaring exhaust note, but even the steering provides better feel than the standard 911.

The 918 Spyder is about more than incredible performance. It proves that a car can be both technologically sophisticated and fun to drive. That, we hope, is the most important part of the 918 Spyder that will work its way into more everyday cars.