|The electric flywheel next to the driver seat. Click to enlarge.|
Porsche unveiled the 918 RSR at the North American International Auto Show, combining the flywheel technology of the 911 GT3 R hybrid (earlier post) and the design of the 918 Spyder. The mid-engine coupé 918 RSR, is the motor sports version of the 918 Spyder concept car.
The V8 engine in the 918 RSR is a further development of the direct injection engine from the successful RS Spyder race car and now offers an output of 563 hp (420 kW) at 10,300 rpm in the 918 RSR. The electric motors on the two front wheels each contribute 75 kW to the peak drive power of 767 hp (572 kW). This additional power, which is generated during braking, is stored in an optimized flywheel accumulator.
The two electric motors offer a torque vectoring function with variable torque distribution to the front axle. This additionally increases agility and improves steering response. Mounted upstream of the rear axle, the mid-engine is integrated with a racing transmission also based on the RS Spyder race car. This further developed six-speed constant-mesh transmission with longitudinally mounted shafts and straight-toothed spur gears is operated using two shift paddles behind the racing steering wheel.
In contrast to the 918 Spyder concept car, an unadorned racing atmosphere predominates in the interior of the 918 RSR. Instead of the futuristic, ergonomically avant-garde centre console with touch-sensitive user interface from the 918 Spyder concept car, the 918 RSR’s cockpit is split by a minimalistic console with rocker switches. Instead of a second seat, the flywheel accumulator is positioned to the right of the console.
In addition to its use in Porsche racing cars, Matthias Mueller, President and CEO of Porsche AG suggested during the press conference at the Detroit show that the flywheel technology might appear be for “road-going cars as well.”