Porsche's 520-horsepower super-sport-utility defies logic and definition
By Chris Walton Email
It was not by accident that Porsche chose to introduce the 2006 Cayenne Turbo S on its own world-class (assembly-line adjacent) racetrack in Leipzig, Germany, as well as in the silty, orange sand dunes outside Dubai in the United Arab Emirates. Why not? Because there is simply no other production vehicle that could possibly manage to perform as well as the 520-horsepower Cayenne Turbo S does in both extreme locations.
"What about the 510-hp Mercedes-Benz ML63 AMG or the 420-hp Jeep Grand Cherokee SRT8?" you ask. While those two might be able to run a competitive lap at the track, neither one is offered with the kind of dedicated off-road hardware (and software) the Cayenne Turbo S has as standard equipment. Besides, its gargantuan power output, locking center differential (optional rear-axle lock), low-range (2.7-to-1 reduction) transfer case and six-way height-adjustable suspension are what differentiate the Cayenne Turbo S from its competitors and make it a unique offering in the ultrasport-utility segment.
And who wouldn't feel anything but glee hammering a nearly 3-ton vehicle around a racetrack (or flying over a dune) at speeds that would seem to suspend the laws of Newton and Euclid? More than a horsepower-fortified sport-ute with the aesthetics of a dented potato, the highly engineered Cayenne Turbo S employs decades' worth of Porsche know-how, track research and pure imagination. Does anybody really need a five-passenger supercar/dune buggy? Probably not, but that doesn't mean you can't want one.
520 horses, or about 1,000 camels
In the Cayenne Turbo S, Porsche increased the already potent Cayenne Turbo's 4.5-liter twin-turbo V8 horsepower and torque 16 and 15 percent, respectively and yet it consumes no more fuel than its 450-hp brother in normal driving conditions. By enlarging and constructing the twin intercoolers entirely of aluminum, the engineers were able to promote higher efficiency and better flow conditions in the heat exchangers. The result is a reduction of turbo pressure loss by 50 percent. This more rigid system in turn allows the turbocharger pressure to be increased by 2.9 psi up to a maximum of 27.6 psi.
In terms of power output among current Porsches, the Cayenne Turbo S is second only to the 605-hp V10 Carrera GT supercar. Porsche claims the 5,200-to-5,900-pound (depending on options) Cayenne Turbo S will run zero to 60 mph in 4.8 seconds, and we have no reason to doubt it. That's a few ticks ahead of what we expect from its nearest competitors.
However, what's most striking about the Turbo S's driving dynamics is the ever present and ever ready wave of torque upon which the vehicle rides. Maximum torque of 530 lb-ft is available from just 2,750 rpm. There's an effortlessness to the way the Turbo S wills itself to any speed the driver chooses. It's the kind of vehicle that requires periodic speedometer checks because it never feels like it's had enough time nor worked hard enough to find itself at triple-digit speed. If the engine does venture north of 4,000 rpm, the guttural response from the exhaust sounds like a caged lion's roar in anticipation of fresh meat.
A ratio for every mood and occasion
Porsche's six-speed Tiptronic S automatic transmission is standard equipment on the Cayenne Turbo S. It offers the driver the option of automatic shifts or manual shifting by nudging the selector lever or by thumbing switches on the steering wheel.
In auto mode, the intelligent system "learns" a driver's habits, observes the incline of the terrain and notices cornering G-loads to tailor and/or delay shifting to maximize comfort or performance. Further, the driver may, at any time, intervene in automatic mode by touching the thumb switches, temporarily summoning the manual mode.
We tried both automatic and manual modes on the racetrack and found that while automatic shifting does, indeed, become more aggressive and sporting with each passing lap, the manual mode was best suited to the demands of the driver, offering better control of the vehicle especially when Porsche Stability Management (PSM) was disabled.
The Porsche Traction Management (PTM) four-wheel-drive system is based on an all-encompassing approach that incorporates a number of different electronic systems and traditional hardware. In simple terms, the engine's power is routed through a central multiplate clutch operated by an electric motor. This clutch apportions power to the vehicle's front and rear axles.
In normal driving, the split is rear-biased at 62 percent to lend a familiar and sporting demeanor. However, unlike similar variable-locking clutch-based systems, PTM can route 100 percent of the drive power to either axle not a maximum of 50 percent to each. Drawing on information gathered from the vehicle's speed, lateral acceleration, steering angle and throttle position, the system constantly adjusts the power split to both axles.
Many manufacturers' systems end there with one system that is optimized for either on- or off-road use. Not Porsche. This system is so highly developed and flexible that it's as useful as an all-wheel-drive sports car as it is as a capable snow (or sand) mobile.
and another set for off-roading
When the pavement runs out, the Cayenne Turbo S is just getting started. With the flick of a switch the reduction gear is engaged and the engine's torque is multiplied 2.7 times. At the same time, PTM, PSM, ABS and automatic brake differential (ABD) are all reset to better manage off-road situations. Should these settings prove insufficient, the driver may operate the same switch again to lock the entire system front-to-rear, thereby driving both axles simultaneously. And if the vehicle is equipped with the Advanced Offroad Technology Package, rocking the off-pavement switch a third time will lock the rear axle's left and right wheels.
If a particularly troublesome obstacle (fallen tree, rock on the trail) presents itself, the front and rear antiroll bars may be electronically decoupled for an additional 2.4 inches of suspension articulation that keeps the vehicle more upright while traversing the hurdle. Additionally, the Cayenne Turbo S features a hill-descent mode wherein the driver removes his feet from both pedals and the Cayenne safely inches its way down a slippery slope at a prescribed speed.
Is something rubbing?
OK, so what's the rub? How about a $112,415 price tag for starters? Porsche is notorious for optional equipment pricing matrixes, with a colored Porsche crest on the wheels' center caps costing an extra $185, for instance. The Offroad Tech Package we loved so much is another $4,290, and the 20-inch wheels/tires pictured here will cost $2,160 more. You get the point, and we can comfortably estimate that the total cost of the Cayenne Turbo S we drove to be $150,000.
Also, we noticed how sensitive the vehicle is to worn tires on the racetrack, where handling was greatly affected by variously new/old tires. Those aren't free, either. Finally, all of our sand-dune slinging was only possible by letting about half the air out of all four tires. Should you choose to replicate our foray, you'll need to have an air compressor handy before returning to civilization.
But then again
You've gotta love that there is a vehicle that can run competitive track laps and also go where only camels have gone before. It should be no surprise that Porsche builds the machine that can do that, while costing you half a fortune. Put a large enough engineering team behind a project and anything is possible. Remember, Porsche is the company that made the 911 a crown jewel, a rear-engined car with the weight distribution of a lead-feathered arrow that flies like one built with perfect weight distribution. Why? Because the carmaker enjoys the heck out of solving riddles with ingenious engineering. Doing with ease what appears to be impossible is what the 2006 Porsche Cayenne Turbo S is all about. It'll humiliate a sports car or four-wheel-drive truck. So, how much should a magic carpet cost? Put it that way, and $112,000 starts to sound if not reasonable, then at least plausible.
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