Porsche 918 RSR – Not Your Average Hybrid

Life has been interesting lately for Wolfgang Dürheimer, to say the least.  The 52-year-old Executive Vice President of Porsche Research and Development made automotive headlines last November when he was appointed Chairman and CEO of Bentley Motors, and President and CEO of Bugatti S.a.S.  But apparently, taking the joint helm of the VW Group’s high profile luxury divisions was not quite exciting enough.  So last Monday, at Porsche’s press conference at the North American International Auto Show in Detroit, Dürheimer (pictured below at left with Porsche President and CEO Matthias Muller) casually rolled out in the manufacturer’s feature attraction, a new concept car dubbed the 918 RSR.

Now if you’re overcome with déjà vu, rest assured that any sensation you may have that we’ve covered this ground before isn’t entirely unfounded.  The 918 RSR is based on the 918 Spyder concept car that we’ve covered in the past, including two weeks ago when the Spyder made my list of Top 5 Supercars of 2010.  Obvious physical differences between the two cars are evident in the new car’s coupe configuration (that is, it has a roof), as well as its large rear spoiler, which in combination with the race livery suggests that the 918 RSR is all about motorsports.  (Its number 22 is, indeed, an allusion to the number worn by the 1971 Le Mans-wining Porsche 917 short-tail coupe.)

The new car may hold the basic shape of the recent 918 Spyder, and from that car it derives the numeric portion of its name, but what of the RSR?  This remainder of the car’s nomenclature is traced to its powertain, which combines the engine of the RS Spyder prototype racecar with the flywheel-powered electric motors of the 911 GT3 R hybrid racecar that debuted last year.  OK, admittedly that’s a lot of different R’s and Spyders in one breath, and the name could just as easily be a nod to any number of RSR cars that have previously appeared during Porsche’s history.  Suffice it to say that the 918 RSR has a 563-horsepower V-8 engine combined with two front-wheel-mounted electric motors that lift total power output to 767 horses – quite a bit of get-up-and-go.

While Porsche calls the 918 RSR a hybrid, the car only relates to the common Prius conception of a hybrid in the loosest sense.  The electric motors in the new Porsche are powered by a flywheel accumulator that actually occupies the passenger area of the cockpit.  This accumulator recycles energy during braking and stores it for future use (not conceptually unlike the regenerative braking so effectively implemented in the Tesla Roadster).  When summoned by a driver-triggered button, the accumulator releases the stored electricity to the front wheels for up to eight seconds of power boost, ideal for extra acceleration or passing maneuvers.  So in summary, that’s eight seconds of electric power, and everything else the good old-fashioned way via an internal combustion engine.  Not exactly what most people have in mind with the term hybrid, but who could dislike this car?