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.
Source - Porsche
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.