tire pressure PORSCHE CAYNNE 2013 2.G Information Manual

Drive systems and chassis | Engine technology · 42
41 · Drive systems and chassis | Engine technology
Compression with precision.
Essential for getting right to the point.
Direct fuel injection (DFI).
DFI injects fuel directly into the combus -
tion chamber at up to 120 bar with milli -
second precision using electromagnetic
injectors. The injector position and spray
geometry have been carefully designed
to improve output, torque, fuel economy
and emissions. The swirling of the fuel as
it enters each chamber increases the
mixing of air and fuel, thereby enhancing
combustion. By forming the air/fuel mix -
ture directly in the combustion chamber,
DFI contributes to engine cooling. As a
result, it was possible to increase the
compression ratio and therefore power
and efficiency.
Direct fuel injection on the diesel
engine (common-rail injection system).
On the Cayenne Diesel, direct fuel injec -
tion comes courtesy of a common-rail
injection system. The injection pressure
is now up to 2,000 bar, ensuring optimum
distribution of the air/fuel mixture – for
greater performance. The piezoelectric
injectors provide flexible injection rate
adjustment, using exactly metered
quantities of fuel, with multiple injections
for each power stroke to deliver smooth
combustion.
Cooling systems.
A high-performance engine can only
maintain its maximum capability over
a long service life if all components are
operating consistently within a specific
temperature range. The engines in the
Cayenne models are therefore designed
for efficient cooling.
In order to reduce the frictional losses
that occur during warm-up, all Cayenne
models feature comprehensive thermal
management. Using intelligent control,
it activates the different cooling circuits
individually and on demand, thereby
ensuring that the optimum operating
temperature for the engine and trans -
mission is reached more quickly. This
minimises friction – and keeps fuel
consumption and CO
2 emissions low.
The V8 engines have an enhanced coolant
management system offering effective
temperature control throughout the engine.
While 20 % of coolant flows longitudinally
through the crankcase, the remaining 80 %
serves the cylinder heads using the proven
cross-flow principle (from hot to cold).
On all Cayenne models, the piston heads
are cooled using oil-spray jets integrated
within the main lubrication system.
The entire cooling system is designed for
prolonged heav y-dut y use, e.g. off-road
driving or heav y towing and carrying
applications.
Lubrication.
The V8 engines use dry-sump lubrication
to ensure a consistent supply of oil in
all load conditions, especially in off-road
terrain. The oil reservoir is located inside
the engine. This saves on space and
reduces weight.
Oil is circulated around the V8 engines
using a demand-driven pump. This has
been designed for the toughest driving
scenarios on and off road, including per -
formance driving and extreme gradients.
The V6 engines have a wet-sump lubrica -
tion system. Ensuring a reliable supply of
oil, whatever the driving conditions.
For fuel consumption, CO
2 emissions and efficiency class data, please refer to pages 150/151.

Drive systems and chassis | Engine technology · 44
43 · Drive systems and chassis | Engine technology
Air intake system.
The Cayenne models are all equipped
with a resonance air intake system.
This technology uses the pressure waves
generated by the inlet valves to ‘ force’ air
into the engine.
The effect is further enhanced on the V6
engine in the Cayenne and the V8 engine
in the Cayenne S and the Cayenne GTS
by a t wo -stage intake manifold. This vari -
able geometry combines all the benefits
of a long intake tube (higher torque at
low rpm) with those of a shorter length
(more power at higher rpm).
The result: highly impressive torque
ratings across the entire engine speed
range.
Turbocharging system in the
Cayenne Turbo.
In the Cayenne Turbo, the engine is
assisted by t win turbocharger units
arranged in parallel – one for each bank
of cylinders. Incoming air is passed
through a filter and compressed by the
turbine units. Its temperature is then
reduced in the twin intercooler system,
which improves cylinder charging and
limits thermal loads on the engine.
Supercharging system in the
Cayenne S Hybrid.

The engine in the Cayenne S Hybrid is
equipped with a supercharger. For a
more direct response, even at low revs
and road speeds. The supercharger has
a low-temperature water cooling system
for cooling the charge air.
Variable Turbine Geometry (VTG) in
the Cayenne Diesel.
The turbocharger in the Cayenne Diesel
features Variable Turbine Geometry
(V TG). The gas-flow from the engine
is channelled onto the turbines via elec -
tronically adjustable guide vanes. By
changing the vane angle, the system can
replicate the geometry in all t ypes of
turbo, large or small, and thus achieve
the optimum gas-flow characteristics.
As a result, even at low engine rpm,
the turbine speed is maximised. For a
significant increase in boost pressure,
excellent cylinder charging plus greater
power and torque.
Electronic engine management.
Cultured performance in all driving
scenarios requires comprehensive
engine control. The electronic engine
management system does this by
continually monitoring the relevant input
data from a variet y of sophisticated
sensors. This data is then compared with
a corresponding set of reference values.
Based on this information, a range of
key engine functions, e.g. ignition and
injection timings as well as injection
quantities, are seamlessly and auto -
matically adjusted. Other major functions
include on-board recuperation. It ensures
that the on-board power supply is only
replenished while the vehicle is on the
overrun. This boosts fuel economy as
well as performance, and ensures max -
imum engine output during acceleration.
All this goes unnoticed by the driver,
apart from the obvious benefits: lower
fuel consumption and CO
2 emissions plus
greater power and torque at all times.
Exhaust system.
The light weight exhaust systems in the
Cayenne models are made from special,
long-life stainless steel. The key features
of the catalysts are high efficiency,
faster warm-up and a long service life.
Sports exhaust system.
Available as an option on the Cayenne
and Cayenne S and included as standard
on the Cayenne GTS, the sports exhaust
system
1) provides an even more distinct -
ive sound. For the looks to match, it
comes with a specially designed set of
t win dual-tube tailpipes with a high-gloss
finish. On the Cayenne GTS, these are
finished in mat t black.
All exhaust systems, standard and
sports, comply with the EU 5 emissions
legislation.
1) For Cayenne only in conjunction with Tiptronic S. Single-tube tailpipes on the Cayenne, Cayenne Diesel,
Cayenne S and Cayenne S Hybrid
Dual-tube tailpipes on the Cayenne Turbo
Sports exhaust system (optional)
But ton for spor ts exhaust system
Spor ts exhaust system, with t win dual -tube tailpipes in mat t black on the Cayenne GTS For fuel consumption, CO2 emissions and efficiency class data, please refer to pages 150/151.