(from Porsche Press Release)
With twin turbochargers boosting the output of its 4.5-liter V8, the Cayenne Turbo
delivers 450 horsepower (SAE) and 457 lb.-ft. of torque, power that propels it
from a standing start to 62 mph (100 km/h) in a mere 5.6 seconds and to a top
track speed of 165 mph (266 km/h).
But the Cayenne Turbo is just as capable off-pavement, thanks to its combination
of Porsche Traction Management with standard air suspension that can provide
nearly 11 inches of ground clearance for traversing rough terrain.
Like the Cayenne S, the Cayenne Turbo comes with such standard equipment as
Porsche Stability Management; a six-speed Tiptronic S transmission; front, side
and curtain airbags; full leather upholstery; and automatic climate controls. The
Cayenne Turbo adds such features as an aluminum-trimmed interior and the new
Porsche Communications Management technology that includes a navigation system
and Bose Cabin Surround Sound System.
The Porsche V8 is an all-new, Porsche-designed 4.5-liter unit with 32 valves (two
intake and two exhaust valves per cylinder), Porsche’s VarioCam® technology, and
integral dry sump lubrication. The two banks of cylinders are placed at a 90-degree
angle. The engines are built at Porsche’s factory in Stuttgart-Zuffenhausen, Germany.
The Cayenne Turbo is powered by a similar 4.5-liter V8, but two turbochargers
recycle the engine’s exhaust gases and boost its power to a staggering 450
horsepower (SAE) at 6,000 rpm and to a whopping 457 lb.-ft. of torque throughout
the 2,250 to 4,750 rpm range.
Because of such higher loads, the Cayenne
Turbo has cylinder heads made of special high temperature-resistant
aluminum alloy similar to that used in Porsche racecars. The intake
ducts are modified for the greater fuel/air mixture, and the cylinder
head features double valve springs on the exhaust side to ensure maximum
engine performance. The Turbo also has special forged pistons and
additional oil cooling jets.
The Porsche V8 engine is designed to
operate smoothly at an angle of 45 degrees off-horizontal, thus
providing optimum off-pavement abilities. This required modification of
the oil circuit and crankcase-venting system, most notably separate oil
re-flow ducts leading from the cylinder heads into the oil sump.
Separation of the oil circuit from the vent ducts enables engine oil to
flow quickly and directly back to the oil sump to maintain a sufficient
oil supply at all times.