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.
· 40 ·· 41 ·The new 911 Turbo |
Drive
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
For maximum manoeuvrability,
PSM can be partially disabled
while the car is still in ‘Sport’
mode. PSM simply monitors the
forces acting on the car and
will only intervene in the most
critical of situations, e.g., when
ABS assistance is required on
both front wheels.
To help you quantify this
increased performance, the
Sport Chrono Package Turbo
includes a swivel-mounted timer
on the dashboard. Functions
are accessed via the control
stalk for the on-board computer.
Analogue dials measure hours,
minutes and seconds, while aseparate digital field displays
whole seconds, tenths and one
hundredths of a second. The
digital field runs in parallel with
a second display which is
conveniently located in the
instrument cluster.
Individual lap times can be
viewed, stored and analysed using
a special ‘performance display’
added to Porsche Communication
Management (see page 86).
Available information includes the
time and distance travelled on
the current lap, as well as the
number of laps completed and
the respective times. The system
can also display the current
fastest lap and remaining range
till empty. Driving times can be
recorded for any stretch of road
and benchmark times can be
defined. Other useful features
include a memory function
accessible via PCM. This can beused to store a range of personal
preferences, such as daytime
driving lights, ‘Welcome Home’
light function, air conditioning,
rain sensor activation and door-
lock mode.
· 62 ·· 63 ·The new 911 Turbo |
Chassis
