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DFI delivers fuel directly into the combustion
chamber with millisecond precision. The
spray and cone angles of the new multi-
hole injectors have been optimised for
torque, power output, fuel consumption,
emissions and ef ficient combustion.
With direct injection, the engine manage-
ment system regulates injection timing
individually for each cylinder as well as
the injection rate for each cylinder bank.
This optimises the combustion process
and fuel economy. operation to the prevailing conditions.
This results in instant acceleration,
extremely smooth running and an
extraordinary level of tractive power,
but with a comparatively low level of
fuel consumption.
For faster heating of the catalytic converters
after a cold start and optimum torque in
the upper load range, up to three injection
pulses take place per combustion cycle.
DFI improves the internal cooling of
the combustion chamber by having the
mixture prepared directly in the cylinder.
This allows for a higher compression
ratio, which helps to deliver more output
at the same time as enhanced engine
efficiency. Injection is regulated by the
electronic engine management system
and emissions are monitored by the
Lambda sensors.
Temperament | Engines
VarioCam Plus System.
VarioCam Plus is a two-in-one engine
concept for adjusting the intake
camshafts and switching the lift of the
intake valves.
The system first dif ferentiates bet ween
driver inputs that typify normal,
everyday driving and those inputs
that demand maximum performance.
The electronic engine management
system then seamlessly adapts valve
What lies between your home and Le Mans?
Advanced engineering as standard.
Direct fuel injection (DFI).
For fuel consumption and CO2 emissions please refer to page 129.
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3839
Temperament
|
Engines
Integrated dry-sump lubrication.
Integrated dr y-sump lubrication ensures
a reliable supply of oil even when a
sport y driving st yle is adopted. It also
has additional cooling functions.
The oil tank is located in the engine,
thereby eliminating the need for an
external oil tank, which saves both space
and weight. To reduce power loss and
increase efficiency, an electronically con -
trolled oil pump supplies the lubricating
points inside the engine as and when
required. This results in optimum supply
of oil, low fuel consumption and, there -
fore, lower exhaust emissions.
Air intake system.
The resonance intake system increases
the intake volume by exploiting the fact
that air oscillates as it passes through
the intake manifold. The system can
adjust to engine speed. Benefits of this
include higher torque at low engine
speeds and a flat ter torque curve.
The
911 Carrera S models operate a t wo -
stage
system.
The entire intake system is made from
light weight plastic. In the new 911 Carrera
model range, the resonator volume of the
air filter housing varies with engine speed
to bring added character to the engine
sound, which becomes much more power -
ful at higher rpm.
Exhaust system.
The exhaust system of the new 911
models has been completely redesigned,
acoustics included.
The stainless-steel exhaust system com -
prises t wo distinctive and independent
exhaust tracts. The cataly tic converters
heat up rapidly for effective emissions
reduction.
A selectable t win -tube sports exhaust
system featuring distinctive polished
stainless-steel tailpipes is available as an
option. Activated by a but ton, it produces
an even more intensive sports car sound.
911 Carrera S with sports exhaust system
Engine management system.
The EMS SDI 9.1 engine management
system ensures optimum engine perfor -
mance at all times.
It controls, for example, the position
of the electronic throt tle valve (ETC) –
a prerequisite for compatibility with the Porsche Stabilit y Management (PSM),
which comes as standard. It also regulates
all engine-related functions to achieve
optimum fuel consumption, emissions and
power output whatever the driving st yle.
Another function is the cylinder-specific
knock control. Since the cylinders never all
work under exactly the same conditions, the knock control function monitors each
one separately. The ignition point is shifted
individually, as and when necessary, to
protect the cylinders and pistons at high
engine speeds.
For compliance with EU standards, the
on - board diagnostics detect any faults
and defects that may occur in the exhaust and fuel systems and then notify the
driver immediately. This also prevents
increased pollutant emissions and
unnecessary fuel consumption.
Twin tailpipe of the sports exhaust system Single-tube tailpipe on the 911 Carrera
Twin-tube tailpipe on the 911 Carrera S
For fuel consumption and CO2 emissions please refer to page 129.
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6667
Composure
| Safet y
Control, discipline, precision.
At Porsche, we take driving pleasure very seriously.
S a f e t y.
Brakes.
Another crucial piece of the Porsche
identit y is the brakes. We value them as
highly as we do our engines and chassis.
They set standards for deceleration and
stabilit y, and give the driver the reassur -
ance needed to push the car to the limits
of its performance.
The 911 Carrera and 911 Carrera Cabriolet
are fit ted front and rear with anodised
black four-piston aluminium monobloc
fixed calipers. All brake discs have a
diameter of 330 mm. On the 911 Carrera S models, we have
fit ted larger brakes and more brake pistons
to cope with the increased engine power
of these models. The new generation of
brakes features red six-piston monobloc
aluminium fixed brake calipers at the
front and four-piston aluminium monobloc
fixed calipers at the rear. The brake
disc diameter is 340 mm at the front and
330 mm at the rear. The results are
enhanced braking performance and a
reduction in stopping distance compared
with that of the previous model.
On all models, the brake calipers have
an enclosed monobloc construction.
This makes them tougher but lighter and enables a more rapid response and
release of the brake even under extreme
loads. The pedal travel is short and
the biting point precise. The brake discs
are cross-drilled for better performance
in the wet.
Other benefits of the standard braking
system include the anti-lock braking
system (ABS), designed to keep decelera -
tion constant. Pedal effort is reduced and
braking response improved by a newly
developed 8-/9-inch tandem vacuum
brake booster. In the S models, brake disc
cooling is further enhanced by modified
air spoilers.
Standard brake system on the 911 Carrera
Standard brake system on the 911 Carrera S