(from Porsche Press Release)
In the Cayenne S, the engine is normally
aspirated yet still provides 340 horsepower (SAE) and makes even the basic
Cayenne S among the strongest of all SUVs. The normally aspirated engine is
rated at 310 lb.-ft. of torque, with maximum power provided all the way from
2,500 rpm to 5,500 rpm.
Working in conjunction with the new six-speed Tiptronic® S
transmission, the normally aspirated 4.5-liter V8 propels the Cayenne S
from a standing start to 62 mph (100 km/h) in only 7.2 seconds. The
Cayenne S can achieve a top speed of 150 mph (242 km/h) on the test
The Cayenne S comes with Porsche Traction Management; Porsche
Stability Management; front, side and curtain airbags; a Bose® Cabin
Surround Sound System; leather upholstery; and automatic climate
The V8 shares much of its internal architecture with the liquid-cooled six-cylinder
engine that was developed to power the Porsche Boxster®. However, Porsche
engineers developed specific components and dimensions for the Cayenne’s new
V8. For example, while the 3.66-inch (93 mm) cylinder bore is the same as the
Boxster’s, the V8 has a longer stroke of 3.27 inches (83 mm). The V8 has a
two-piece cylinder head similar to that developed for the powerful 911 Turbo,
and the Cayenne engine’s cylinder head makes use of an aluminum/silicon alloy
that can withstand very high temperatures.
As with all other Porsche models, the new V8 makes use of Porsche’s VarioCam®
technology. For the Cayenne’s V8, VarioCam can adjust the intake camshafts by as
much as 25 degrees, ensuring outstanding torque characteristics as well
as optimum fuel efficiency and lower emissions.
Engine coolant is distributed to the
crankcase and cylinder heads by a distribution pipe located above the
transmission. The water pump, mounted at the front of the engine, pumps
coolant through a pipe located in the interior of the engine’s V.
Approximately 20 percent of the coolant flows through the crankcase in a
lengthwise direction with 80 percent flowing through the cylinder heads
in a “cross flow” architecture from the hot to the cold side. Heat from
the engine oil is fed into the coolant through an oil/water heat