Ferrari's limited-edition supercars are special. They appear
about once a decade, cost a small fortune -- which has never hurt sales -- and
often become the benchmark for next-generation supercars at Ferrari and in the
industry.
Ferrari Chairman Luca Cordero di Montezemolo says the new
LaFerrari is no exception because of features such as the supercar's
gasoline-electric hybrid powertrain, its Formula One-inspired carbon fiber
cockpit and its state-of-the-art active aerodynamics.
Despite a pretax sticker price of $1.3 million, Ferrari sold
out its 499-unit run of the supercar before its world debut in March at the Geneva motor show.
Montezemolo said the company had more than 700 requests to buy a LaFerrari,
which carries a name that the chairman picked despite internal skepticism.
"We chose to call this model LaFerrari [Italian for The
Ferrari] because it is the finest expression of our company's unique,
unparalleled engineering and design know-how, including that acquired in
Formula One," Montezemolo said.
Automotive News Europe spoke with the men responsible for
LaFerrari's engineering and design. Here is an in-depth look at some of the
challenges faced en route to delivering the company's fastest, most
technologically advanced road car.
Cutting-edge ideas
"Replacing the Enzo was far from easy," said
Roberto Fedeli, Ferrari's technical director.
The carbon fiber Enzo, launched in 2002, was powered by a
6.0-liter V12 engine that delivered 660 hp and accelerated from 0 to 62 mph in
3.6 seconds.
"Ten years later, there is no way that we would have
allowed ourselves to make just a small step forward from the Enzo," Fedeli
said, adding that one of the best parts about developing LaFerrari was the
chance to take cutting-edge ideas from the drawing board into the car.
Ferrari knew that the Enzo's replacement had to be the same
weight or lighter. The first step toward this goal was a research model
unveiled in 2007 called the Millechili. Ferrari developed the car to test ways
to shave 584 pounds from the 3,009-pound Enzo.
To do this, Ferrari decided to make LaFerrari about 35.4
inches shorter than the Enzo's 185 inches and downsize the engine to a
3.0-liter twin-turbo, gasoline direct injection V8 with 550 hp.
Although Fedeli and his team supported the engine switch,
which would have cut more than 198 pounds, the company later decided that its
next-generation supercar had to have a normally aspirated V12. Period.
Making Fedeli's bid to maintain or cut weight even tougher
was Ferrari's decision to equip its next supercar with a hybrid powertrain
derived from Formula One's Kinetic Energy Recovery System, or KERS.
"We wanted to use the hybrid technology to boost
performances, like in F1, rather than use it just to reduce fuel consumption
and emissions," Fedeli said.
When development of Ferrari's HY-KERS system started in
2009, Ferrari predicted the hybrid's parts would add about 441 pounds because
of the electric motors, batteries and wiring. By the time Fedeli's team was
done with LaFerrari, the HY-KERS system's weight was down to 330 pounds. The
electric motors and control systems weighed about 132 pounds, the batteries 198
pounds.
That was just one of the methods to make sure LaFerrari
would match the Enzo's weight.
On a diet
Another key was having Ferrari's Formula One team build the
cockpit using the same grade of materials and the same construction used for
the company's race cars.
The resulting carbon fiber cockpit weighs just 154 pounds,
66 pounds less than in the Enzo's.
Another way Ferrari limited LaFerrari's weight was by
eliminating its seat structures, a solution first tried with the Millechili
research car. The driver and passenger of LaFerrari sit on upholstery that is
fixed to the carbon fiber cockpit. Instead of moving the seat, the driver
adjusts the pedals and steering wheel. This solution also let Ferrari shorten
the passenger compartment because there was no need to make room for seats
moving farther back on rails.
"Between the elimination of traditional seats and a
smaller passenger compartment, we saved another 110 pounds," Fedeli said.
The single-minded focus on weight also led Ferrari to use
lighter body paint, which saved 15.4 pounds, and superthin carbon fiber body
panels, which cut another 22 pounds.
Along with finding ways to limit weight, Ferrari engineers
looked to optimize the HY-KERS system, which uses two electric motors developed
by Magneti Marelli. One motor powers the wheels while the other powers the
car's ancillary systems.
"Every time you accelerate, the electric motor's 120
kilowatts [equivalent to 163 hp] work together with the 800 hp from the
6.3-liter V-12 engine. The result is an acceleration boost never before seen in
a road car," Fedeli said.
Ferrari said the high torque levels available at low
revolutions from the electric motor enabled the engineers to optimize the
internal combustion engine's performance at higher revs. The LaFerrari redlines
at 9,250 rpm. Total torque generated by the engine and the electric motor
exceeds 664 pounds-feet. By comparison, the Ferrari F12 Berlinetta delivers 509
pounds-feet.
While LaFerrari replaces the Enzo, its performance benchmark
was the F12 Berlinetta, which debuted last year and raised the bar considerably
from the Enzo. For instance, the F12 Berlinetta needed just 1 minute and 23
seconds to complete a lap at the Fiorano test track, which was 3 seconds
quicker than the Enzo.
With help from the HY-KERS system, LaFerrari's lap time at
Fiorano was 1 minute and 20 seconds, making it 3 seconds quicker than the F12.
LaFerrari also needs less than 3 seconds to accelerate from 0 to 62 mph, less
than 7 seconds to go from 0 to 124 mph and 15 seconds to go from 0 to 186 mph.
Fedeli said that although performance statistics are
important, he is most proud of the "emotion and feeling" that
LaFerrari drivers experience behind the wheel.
Not a plug-in
Fedeli pointed out that LaFerrari is not a plug-in hybrid.
The batteries are charged in two ways: during braking and every time the
internal combustion engine produces more torque than required, such as in
cornering.
"Rather than cutting off the engine, we store the
excess energy in the batteries so that energy can be used to provide a boost
the next time the driver accelerates," Fedeli said.
Technically, LaFerrari can travel 9 to 14 miles in pure
electric mode, but Ferrari has limited the top speed in full battery mode to 3
mph to discourage drivers from trying to use the supercar as a zero-emission
vehicle.
"You can exit the garage in pure battery mode, but
that's it. This car is designed for extreme performances," Fedeli said.
LaFerrari has slashed carbon dioxide emissions to 330 grams
per kilometer, down from the Enzo's CO2 output of 545 g/km and below the 350
g/km of the F12 Berlinetta. The CO2 decrease comes mainly from optimizing
LaFerrari's internal combustion engine, Fedeli said.
When driving, the HY-KERS system disconnects only when the
car reaches its full speed of about 217 mph. At this point, all 800 hp
generated by the V-12 goes straight toward powering the wheels.
Fedeli said that few LaFerrari buyers will notice this
because even on a Formula One race track such as Monza, the supercar reaches
"only" 170 to 180 mph at the end of the main straightaway.
Designed in-house
LaFerrari is the first Ferrari production model designed
in-house and the first in 40 years created by a company other than Pininfarina.
Leading Ferrari design is Flavio Manzoni, a 47-year-old
Italian who took charge of Ferrari's styling department in January 2010 after
working three years as creative design director for the Volkswagen, Skoda,
Bentley and Bugatti brands. Before that, Manzoni worked at Lancia, Seat and
Fiat.
Along with leading the Ferrari design team, Manzoni oversees
any work done by Pininfarina. During the creation of LaFerrari, the automaker's
in-house team won a tense design competition against Pininfarina for the right
to style the supercar. The competition started in October 2010 with 10 1:4
scale models. The next round, which came in April 2011, featured five
full-sized styling models used to show different potential shapes for
LaFerrari. Three models were from Ferrari's team and two from Pininfarina.
"Ferrari management decided to proceed with two
in-house styling models, one internally called Manta, like the fish, the other
called Tensostruttura," Italian for tensile structure, Manzoni said.
In July 2011, the Ferrari styling center built another
full-sized styling model that had two different sides that showed different
interpretations of the Tensostruttura theme. The aim was to find the best
combination of aesthetics and aerodynamic performance.
A seventh full-sized model was built in May 2012. The model
underwent minimal design changes, mainly in the rear. In August 2012,
LaFerrari's final exterior design was frozen.
Manzoni said two goals drove his team: "Everything we
did on styling was guided by aerodynamic inputs and by an intense desire to
save weight. What was not absolutely necessary simply had to go."
Supercars often look aerodynamic, but need huge spoilers and
tall rear wings to add the necessary down force to remain stable at high
speeds.
LaFerrari has active aerodynamic devices such as diffusers
and a guide vane on the front underbody and diffusers and a rear spoiler at the
rear. These generate down force when needed without compromising the car's
overall drag coefficient. The devices deploy automatically according to
performance parameters that are monitored in real time by the car's dynamic
vehicle controls.
"We tried to design a shape that intimately interacts
with the aerodynamic fluxes," Manzoni said, "rather than fighting
against them."
source: http://www.autoweek.com/article/20130506/CARNEWS/130509886by Luca Ciferri
No comments:
Post a Comment