Porsche 911 Turbo User Handbook Manual page 20

Engine cooling. Engine management.
An advanced cross-flow water- In the 911 Turbo, an electronic
cooling system channels coolant brain assures optimal performance
separately to each individual in all operating conditions. The
cylinder, so that all six cylinders Motronic ME 7.8.1 is the latest
operate within the same generation of Porsche's well-
temperature range. Consistent proven engine management
temperatures reduce the chance system. This powerful system is
of pre-ignition knocking, extend responsible for all engine-related
valve life, improve fuel economy functions and assemblies (see
and lower emissions. Cleverly, diagram). Key among these are
the coolant channels are cast Variable Turbine Geometry (VTG),
into the block, eliminating the VarioCam Plus, the electronic
need for hoses and related throttle system and Porsche
maintenance. Waste heat from the Stability Management (PSM). The
oil is transferred to the coolant results: optimal economy,
via two oil/water heat exchangers. emissions and performance,
Coolant is routed through twin regardless of driving style.
radiator units located ahead of
the front wheels and a third unit Another important task performed
placed in the car's nose. by the engine management
system is cylinder-specific knock
control. By preventing pre-ignition
at high engine speeds, it can avert
costly damage to the pistons
and cylinders.
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Input data
Engine speed (from crankshaft)
Camshaft phase angles
Engine load
Pressure upstream from throttle
Throttle-valve angle
Throttle-pedal position
Lambda signal
Knock sensor signal
Temperatures
– coolant
– airflow upstream from throttle
– engine oil
– air in engine compartment
– ambient air
Vehicle speed
Air conditioning settings
Engine immobilizer status
Clutch pedal switch
Ambient air pressure
Exhaust-gas temperature
Moment interface to Porsche
CAN interface to transmission
Stability Management (PSM)
The 911 Turbo I Performance
Used to regulate/control
Ignition
Fuel injection
Throttle valve
Heating elements in Lambda sensors
Fuel pump
Fuel-tank venting
VarioCam Plus
– camshaft phase angle
– valve lift control
Electronic controller for
Variable Turbine Geometry (VTG)
Bypass valve
Secondary air injection
Engine-bay fan
Starter
Onboard diagnostics
Air conditioning compressor
Interface to instrument cluster
Radiator fans
CAN interface to
all-wheel-drive control unit
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