· 32 ·· 33 ·
Boxster and Boxster S
Lightweight construction.
Both Boxster models are equipped
with alloy engines. Ingenious
design down to the finest detail
has enabled weight – and conse-
quently fuel consumption – to be
reduced. Integrating the camshaf t
bearings fully into the cylinder
heads is just one example of the
ef fective light weight construction
measures that have been imple -
mented.
Integrated dry-sump lubrication.
Integrated dry-sump lubrication
guarantees a reliable oil supply
while reducing engine tempera -
tures, even in sportily driven cars.
The oil reservoir is located inside
the engine. Four oil pumps trans -
port the oil from the cylinder heads
directly into the oil sump. A fif th
pump in the oil sump directly sup -plies the lubricating points in the
engine. To reduce power losses
and increase efficiency, an elec
-
tronically controlled oil pump
supplies the engine lubrication
points as and when required.
This means that the oil pump does
not work so hard when there is
less demand for lubrication. The
benefits of an on-demand oil
supply system are optimum effi -
ciency combined with a reduction in both fuel consumption and
CO
2 em issio ns.
For the engine, these detailed
solutions mean a consistent
oil supply, regardless of gravita -
tional loads, even in the most
demanding track conditions.
Engine cooling system.
Our cross-flow cooling system,
as used in motorsport, supplies
each cylinder uniformly with cool -
ant. Valves are thus protected
against overload and premature
wear, which minimises the
engine’s tendency to knock and
reduces emissions, fuel con -
sumption and engine noise.
Boxster | Drive
· 34 ·· 35 ·
Boxster
Boxster
Boxster
Engine management system
with electronic throttle.
The electronic engine manage -
ment system ensures optimum
engine performance under all
operating conditions. It regulates
all engine-related functions and
assemblies (see diagram). The
results: optimum performance
and torque with reduced fuel con -
sumption and emissions.
Another important function of the
system is cylinder-specific knock
control. Since the six cylinders
never all work under precisely
the same conditions, they are
monitored individually by the
knock control. If necessary, the
ignition point is shifted individu -
ally to protect the cylinders and
pistons at high engine speeds
and loads. The on-board diagnos -
tics, which are compliant with
European standards, ensure
timely detection of any faults and
defects that may occur in the
exhaust and fuel system in good
time and notify the driver
immediately. This also prevents
increased pollutant emissions
and
unnecessary fuel consumption.
Two-stage resonance intake
manifold.
The intake manifold with dual-flow
distributor pipe has an adjustment
valve which closes and opens at
set engine speeds. A t wo -stage
tuning effect creates oscillation
of the air mass in the intake
system, which in turn generates
a turbocharging effect and opti -
mises induction.
These t wo effects combine to
produce higher torque at low
engine speeds, a flat ter torque
curve, and increased power
output at high engine speeds.
The acoustic properties of the
system are second to none,
producing the characteristic
Boxster sound.
Boxster | Drive
Input data Used to regulate/control
Engine management system
ME 7.8/Boxster – SDI 3.1/Boxster S
Engine load
Lambda sensor signals
Engine speed (from crankshaft)
Inlet camshaft phase angle
Knock sensor signals
Vehicle speed
Pressures
– Engine oil
– Fuel
– Ambient air
Air-conditioning settings
Accelerator pedal
Temperatures
– Coolant
– Intake air
– Air in engine compartment
– Engine oil
– Ambient air
Ignition
Heating of lambda sensors
Fuel pump (Boxster)/fuel pumps
controlled on - demand (Boxster S)
Camshaft position
Fuel-tank venting
Engine fan
Starter
Continuously variable oil pump
Fuel pressure (Boxster S)
Throttle valve
Throt tle -valve angle
Idling via throttle valve
and ignition
Manifold injection (Boxster)/
direct fuel injection (Boxster S)
Valve lift switchover
(VarioCam Plus)
Secondary-air injection (Boxster)
CAN inter face with driving dynamics control, transmission control, immobiliser, instrument cluster, climate control,
SPORT button, SPORT PLUS button, sports exhaust system button, diagnostics, etc.
