hp engine, 767 hp total
(from Porsche Press
Release) Porsche 918 RSR – racing laboratory with even
higher-performance hybrid drive
Stuttgart. Dr. Ing. h.c. F. Porsche AG, Stuttgart, is continuing to
extend its performance and high efficiency competence via intensive
development work in the field of hybrid technology. With the Porsche
918 RSR, the manufacturer of sporty premium vehicles is presenting a
high-end synthesis of 2010's successful hybrid concepts. The
two-seater mid-engine coupé 918 RSR clearly reveals what happens
when the technology fitted in the 911 GT3 R hybrid and the design of
the 918 Spyder are transferred to a modern, innovative super sports
With its highly-efficient flywheel accumulator, the 911 GT3 R hybrid
racing car proved to be an attention magnet during competition
racing on the Nürburgring Nordschleife circuit, during the American
Le Mans Series races (ALMS) in Road Atlanta/USA and the ILMC run in
China's Zhuhai. It demonstrated its massive performance potential
under realistic motor racing conditions against top competitors. The
911 GT3 R Hybrid, referred to internally as the "Race Lab" actually
surpassed the high expectations of Porsche Motorsport.
Competitiveness, high reliability and exemplary fuel efficiency
combined with top performance underscored the Porsche technicians'
basic idea of generating additional power in an intelligent manner.
The 911 GT3 R Hybrid obtains its additional power from its own
vehicle dynamics when braking. Porsche is now transplanting this
technology into the mid-engine coupé 918 RSR, the motor sports
version of the 918 Spyder concept car.
From the tradition established by classic Porsche long-distance race
cars such as the 908 long-tale coupé (1969) and the 917 short-tail
coupé (1971), the Porsche designers created a link to the
postmodernism of the "form follows function" philosophy. In the 918
RSR, the lines' elegant flow is dominated by muscular wheel arches,
dynamic air intakes and a pulpit-like cockpit. A visible fan wheel
between the ram air intake tubes and a rear spoiler with RS Spyder
dimensions additionally emphasise the racing laboratory function.
The new "liquid metal chrome blue" colour which has been created
underscores the sculptured curves of the forms, whilst the typical
Porsche hybrid orange colour on brake calipers and the body's
longitudinal stripes lends remarkable touches.
Motor racing technology also dominates within the particularly
light, torsionally stiff carbon fibre-reinforced plastic (CFRP)
monocoque. The V8 engine is a further development of the direct
injection engine from the successful RS Spyder race car and now
offers an output of precisely 563 hp at 10,300/rpm in the 918 RSR.
The electric motors on the two front wheels each contribute 75 kW,
i.e. a total of 150 kW, to the peak drive power of exactly 767 hp.
This additional power, which is generated during braking, is stored
in an optimised flywheel accumulator.
In the 918 RSR, 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.
The vehicle's functional equipment underscores its puristic motor
racing character. Whether it be the characteristic doors which open
obliquely upwards, the air intake in the roof between the wing
doors, the quick-action locks on the front and rear CFRP lids, the
two roof-mounted aerials for pit radio and telemetry, the RS Spyder-like
small, lateral front flics or the air splitters beneath the front
lip or no-profile racing slicks on 19" wheels with central locking,
the vehicle can be clearly recognised as an experimental racing
In contrast to the 918 Spyder concept car, unadorned racing
atmosphere predominates in the interior of the 918 RSR. The
figure-hugging bucket seat's brown leather covering cites the
history of the gentleman driver; the gear flashes on the racing
steering wheel and a recuperation display on the steering column in
front of the display screen supply the pilot with information.
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.
This flywheel accumulator is an electric motor whose rotor rotates
at up to 36,000 rpm to store rotation energy. Charging occurs when
the two electric motors on the front axle reverse their function
during braking processes and operate as generators. At the push of a
button, the pilot is able to call up the energy stored in the
charged flywheel accumulator and use it during acceleration or
overtaking manoeuvres. The flywheel is braked electromagnetically in
this case in order to additionally supply up to 2 x 75 kW, i.e. a
total of 150 kW, from its kinetic energy to the two electric motors
on the front axle.
This additional power is available for around eight seconds when the
system is fully charged. In the successful 911 GT3 R Hybrid, this
additional power can also be used as a consumption aid depending on
the racing situation, e.g. to delay pit stops or reduce the fuel
tank volume and therefore the weight of the vehicle.
With the new 918 RSR racing laboratory, Porsche is now elevating
this motor racing hybrid concept to an experimental level. In the
918 RSR, "Porsche Intelligent Performance" equates to research into
methods for further sustainable efficiency improvement under the
intensified conditions of the race track, lap times, pit stops and
reliability – a metier in which Porsche has been demonstrating its
success for over 60 years.
Finally, the starting number, 22, pays homage to the anniversary of
a further triumph. Back in the days when overall victories in Le
Mans were not yet an entirely routine matter within the Porsche
racing department, the pilots Dr. Helmut Marko and Gijs van Lennep
were the first to cross the finishing line in 1971's 24-hour
classic. The distance record set by their Porsche 917 short-tail
coupé – 5335.313 kilometres (3315.21 miles) at an average speed of
222.304 km/h (138.13 mph) – did not remain unbeaten for an eternity,
but for exactly 39 years until 2010. At the time, the 917 in the
Martini colours was also an experiment and far ahead of its time: a
magnesium space frame set new standards in Porsche's lightweight