It’s become clear Porsche is all-in with hybrids. The company rolled into the Geneva Motor Show with the 918 plug-in hybrid supercar concept, which followed right on the bumper of the 911 GT3 R Hybrid slated to compete in the 24-hour race at the Nürburgring. For the faithful fearing the dilution of a company built on a reputation for racing, fear not. Porsche is experimenting with hybrids, but it isn’t looking to chase Prius market share.
If the performance figures Porsche’s claiming don’t convince you of that, perhaps a look under the body will. The designers from Zuffenhausen, Germany, have released several cutaway drawings, more details and a video showing the 918.
First, we need to note that all of specs and performance figures are claimed specs and performance figures provided by Porsche — no one’s actually driven the cars. That said, the company is famously conservative with its claims, and the 911 GT3 R Hybrid is headed for the track, so we’ll know soon enough if that car measures up to the hype.
The gorgeous 918 Spyder could be called a plug-in version of the amazing Carrera GT with a few differences. It pairs an electric drivetrain with a mid-mounted V8 engine derived from the 3.4 liter V8 used in the RS Spyder race car. Porsche claims the engine in the 918 produces more than 500 horsepower at 9,200 rpm.
The electric drive uses a liquid-cooled lithium-ion battery pack located behind the seats. Of course, there’s regenerative braking to send energy back to the pack. The electric motors and V8 send power to the rear wheels through a seven-speed Porsche-Doppelkupplungs-getriebe (PDK) gearbox. Up front, the power hits the wheels through a fix transmission ratio.
The 918 has four driving modes: E-Drive is purely electric and provides a range of about 16 miles. Hybrid Mode relies upon the motors and engine in parallel like other hybrids as circumstances dictate, and it has to be the mode for which Porsche claims the car gets 78 mpg. Sport Hybrid mode ups the performance by relying more heavily on internal combustion. And Race Hybrid is for flat-out fun, Porsche’s attempt to prove hybrids can improve performance and fuel efficiency.
Flip the switch to Race Hybrid when you’ve got a full battery and you can use a “push-to-pass” button on the steering wheel to get more than 40 percent extra oomph. You’ll get 500 horsepower from the V8 and an additional 215 horsepower from the electric motors. Master the use of the right pedal and boost button and Porsche claims you can go around the ‘Ring in less than 7:30.
Porsche is also staying true to its racing roots by building the 911 GT3 R Hybrid. It uses an electrical flywheel power delivery system sitting next to the driver to power the two electric motors on the front axle.
Under braking, the electric motors up front will power the flywheel, spinning it up to 40,000 rpm. The kinetic energy of the flywheel can then be used with the push of a button by the driver. If the driver needs a little boost coming out of a corner or for a pass, there will be an additional 162 horsepower available for six to eight seconds. While the flywheel power system does provide a power boost, it can also be used to conserve fuel, something that often is the difference between winning and losing in endurance racing.
Porsche begins testing the 911 GT3 R Hybrid soon to prepare for its racing debut at the 24 Hours on the Nordschleife on May 15 and 16. Porsche is hedging its bets by saying the focus will not be on winning the race but testing and developing the technology. But Porsche likes winning, so we don’t suspect it will tip-toe around the 15.8-mile course.
By Jason Paur
http://www.widowracing.com
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