Lightweight design.
The six-cylinder boxer engine is
a highly compact unit offering
excellent cylinder charging and
torque characteristics as well
as optimum balance and minimal
vibration. With the cylinders
arranged horizontally on either
side of the crankshaft, the
layout is key to the car’s low
centre of gravity.
The alloy crankcase consists
of two main sections, each
containing one bank of cylinders.
The crankshaft runs in eight main
bearings and is driven by forged
connecting rods. For optimum
durability, we’ve used forged
aluminium pistons running in
Nikasil-coated aluminium liners
and featuring individual oil-spray
cooling. Key benefits include lower
frictional resistance and longer
service life.
The cylinder heads are made
from a lightweight alloy which
is extremely resistant to high
temperature. Each bank of
cylinders has two overhead
camshafts driving a set of four
valves – two inlet and two exhaust
– on each individual cylinder.
The valves are arranged in a ‘V’
configuration and feature a highly
efficient dual-spring design.
Engine performance is further
enhanced with the aid of bothVariable Turbine Geometry (VTG –
see page 32) and VarioCam Plus
(variable valve timing and lift
on inlet side – see page 38). The
benefits are not only greater
power and torque, but also better
fuel economy and lower emissions.
Dry-sump lubrication.
This classic dry-sump system
with separate oil reservoir
ensures consistent oil pressures
throughout the engine. In doing
so, it compensates for even the
most extreme and prolonged
gravitational loads.
After passing through the engine,
every drop of oil is returned
directly to the external reservoir.
The flow is driven by two pairs of
scavenge pumps in the cylinder
heads and a further two pumps in
the crankcase. Gas is removed
from the returning oil by means of
a defoaming device in the
reservoir. As a result, the oil
level in the reservoir remains
virtually constant at all times.
The oil is returned to the
lubrication points in the engine
by means of a dedicated
oil-feed pump. With a further
scavenge pump in each of the
twin turbocharger units, the
new 911 Turbo has a total of nineseparate pumps to drive the
lubrication system.
The oil level can be checked from
inside the car via the standard
on-board computer. This solution
is not only cleaner and more
convenient than a conventional
dipstick, it is also significantly
more accurate.
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Main rotating assembly and valve gear
Engine cooling.
The 911 Turbo engine features
cross-flow water cooling with fully
integrated coolant management.
This technology ensures a
consistent flow of coolant to each
of the engine’s cylinders. All
coolant passages are integral to
the block, thus eliminating the
need for external hoses. Each
cylinder receives a fresh supply
of coolant which has not been
pre-warmed by the engine. As well
as improving reliability, this
helps to minimise maintenance
requirements. Waste heat from
the oil is transferred to the
coolant via two oil/water heat
exchangers. The coolant is routed
through twin radiator modules
ahead of the front wheels and a
centrally placed unit in the nose.
Engine management.
Optimum performance is assured
at all times with the aid of
the Motronic ME7.8.1 engine
management system. On the new
911 Turbo, this powerful ECU is
responsible for all engine-related
functions and assemblies (see
diagram). Key among these are
the Variable Turbine Geometry
(VTG), VarioCam Plus and
electronic throttle system – one
of the essential prerequisites
for the standard Porsche Stability
Management (PSM). The results:
optimum economy, emissions
and performance, regardless of
driving style.Another important task performed
by the engine management
system is cylinder-specific knock
control. By preventing pre-ignition
at high engine speeds, this
function can avert costly damage
to the pistons and cylinders. Since
temperatures tend to vary in
different parts of the engine, each
cylinder is monitored separately.
If a risk is detected, the individual
ignition timing is adjusted.
The EU-compliant on-board
diagnostics system provides
continuous fault detection and
early warning for the exhaust
and fuel supply systems. The
resulting benefits are active
prevention of harmful emissions
as well as consistent rates of
fuel consumption.
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Input data Used to regulate /control
Engine management system
(Motronic ME7.8.1)
Engine load
Pressure upstream from throttle
Throttle-valve angle
Engine speed (from crankshaft)
Camshaft phase angles
Throttle-pedal position
Lambda signal
Knock sensor signal
Ignition
Fuel injection
Throttle valve
Heating elements in lambda sensors
Fuel pump
Fuel-tank venting
CAN interface to
all-wheel drive control unit CAN interface to transmissionMoment interface to Porsche
Stability Management (PSM)
VarioCam Plus
– camshaft phase angle
– valve lift control
Electronic controller for
Variable Turbine Geometry (VTG)
Bypass valve
Secondary air injection
Engine-bay fan
Starter
On-board diagnostics
Air-conditioning compressor
Interface to instrument cluster
Radiator fans
Vehicle speed
Air-conditioning settings
Engine immobiliser status
Clutch pedal switch
Ambient air pressure
Temperatures
– coolant
– airflow upstream from throttle
– engine oil
– air in engine compartment
– ambient air
Exhaust-gas temperature
Fuel injection.
Fuel is supplied to each of the six
cylinders by means of sequential
fuel injection. The timing of each
injection and the volume supplied
to each bank of cylinders are
controlled by the Motronic ME7.8.1
engine management system.
Adjustments are based on a range
of variables, such as throttle
position, engine speed, boost
pressure, coolant temperature
and exhaust gas composition. Theresults are optimised combustion
and fuel consumption. A hot-film
air mass sensor monitors the
density of the incoming air to
ensure the optimum air/fuel
mixture, regardless of weather
and altitude.
Ignition system.
The 911 Turbo is equipped with
a static high-voltage ignition
system. Each individual plug has
a separate ignition coil, ensuring
perfect combustion every time.
The role of distributor is performed
by the engine management
system, which operates the coils
directly. The result: optimum
performance with minimal fuel
consumption.
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are reduced thanks to lengthy
replacement intervals for both
the engine oil (18,000 miles) and
air filter unit (36,000 miles). The
spark plugs require changing after
36,000 miles or a maximum of
every four years. The generator,
power-steering pump and air-
conditioning compressor are all
driven by a single self-adjusting
belt with a service life of 54,000
miles. The hydraulic tappets
provide automatic adjustment of
all valve clearances, while the
drive chains on the camshafts
and auxiliary shafts will also last
the life of the car.
Basic servicing is required after
18,000 miles or a maximum of
two years on the road. The first
major service is due at 36,000
miles or every four years at the
latest. The results: lower running
costs and virtually uninterrupted
enjoyment from your Porsche.
Exhaust system.
The exhaust system on the
911 Turbo is made from highly
durable stainless steel. The
system consists of two separate
tracts, one for each bank of
cylinders. The catalytic converters
are extremely heat-resistant,
yet quick to reach temperature
(and thus optimum performance)
when the engine is started
from cold.Twin lambda sensors in each of
the exhausts enable continuous
monitoring of the combustion
process. An additional pair of
sensors* is used to measure
the efficiency of the catalytic
converters.
Servicing.
Another pleasant surprise on the
new 911 Turbo is the standard
service schedule. Running costs
The new six-speed manual
gearbox in the 911 Turbo is
specifically adapted to the car’s
high levels of engine torque.
Designed primarily for sports
driving, one immediate
characteristic is the perfectly
judged spread betweensuccessive ratios as you upshift
through the gears. The gearshift
throw is short and precise,
with only minimal force required.
Thanks to a dual-mass flywheel,
this uncompromising setup means
there’s never any compromise
in comfort. The linkage provides
a direct connection with the
gearbox while insulating
the lever from engine vibration.
One final detail – the new gear
lever design – is exclusive to
the 911 Turbo.
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Six-speed manual gearbox.
Superlative power requires equal precision.
Gear lever exclusive to 911 Turbo* Not in markets with leaded fuel.