Cayenne's balance of style, performance, and sport-utility virtues were compelling, and it quickly became a success story for the small manufacturer of legendary sports cars.When Porsche launched Cayenne as a 2003 model, executives said they hoped to sell 20,000 of the SUVs a year.Clearly, these projections were conservative.In some years Porsche sold more than 50,000 Cayennes.More than 150,000 have been sold in the past four years.Following a redesign for 2008, sales have again increased, making the Cayenne a boon for Porsche's financial planning.Cayenne's ongoing success smoothes over wildly fluctuating sports car sales, which tend to follow the consumer confidence index.Cayenne's success is helping Porsche do what enthusiasts want: develop and build great sports cars and a new four-door sport sedan.Enough hand-wringing already.

For 2009, Porsche has returned the Turbo S version and announced the 2010 Transsyberia Cayenne that goes on sale in Spring of 2009; the Cayenne GTS formally debuted late in 2008.With major advancements made for the 2008 model year, the 2009 primarily adds more extreme examples.

Grabbing headlines is the 2009 Porsche Cayenne Turbo S, boasting 550 horsepower and 553 pound-feet of torque from its twin-turbocharged 4.8-liter V8 and capable of propelling this SUV from 0-60 mph in just 4.7 seconds.It's the fastest Cayenne and most expensive, almost 2.8 times the price of a base Cayenne.

Although it isn't as fast as a Cayenne Turbo, the GTS is the most agile and lithe, with all the suspension tricks of the Turbos, huge tires and wheels, big brakes, and 300 pounds less weight to haul around.The GTS is the only Cayenne V8 offering a choice of manual or automatic transmissions.

We find any Porsche Cayenne enjoyable to drive, smooth, stable, and responsive.It inspires confidence and we felt comfortable driving it right to and beyond grip levels on a gravel road.It's easy to control and predictable and always behaves as expected.

Cayenne comes with a 3.6-liter V6 (290 hp, 273 pound-feet of torque).Leather seating with 12-way power adjustment comes standard, along with titanium-look interior trim; manually controlled climate control with charcoal and micro-particle cabin filtration; heated folding exterior mirrors; multi-function trip computer; 12-speaker stereo with CD; air conditioned glove compartment; cruise control; insulated laminated privacy glass; Homelink; immobilizer anti-theft alarm; and an electronically latching power tailgate.

Cayenne S gets a 4.8-liter V8 (385 hp and 369 lb-ft) and 18-inch wheels.Cayenne S adds automatic climate control with dual front-passenger settings and a 350-watt, 14-speaker Bose stereo.

Cayenne GTS spins the 4.8-liter V8 up to 405 hp and adds shorter gearing, lower-ride-height air suspension with Porsche Active Suspension Management (PASM), big brakes, 21-inch wheels with 295/35 tires, power tilt/telescope wheel, sport seats front and rear with Alcantara inserts, more aggressive bodywork and light-tube front signal/marker lamps.

Cayenne Turbo features a twin-turbocharged version of the V8 (500 hp and 516 lb-ft).The Turbo comes standard with an adjustable air suspension with PASM, heated front and rear seats, and park-assist radar warning front and rear.It's equipped with Porsche Communications Management (PCM), a GPS navigation system with integrated telephone and audio controls, and headlights that turn with the steering wheel.

Cayenne Turbo S bumps power to 550 hp and 553 lb-ft and adds Porsche Dynamic Chassis Control (active suspension), ceramic composite brakes, 21-inch wheels, and most luxury amenities.

Options are extensive with fewer available as the base price increases, but even Turbos offer plenty of them.In Porsche fashion you can order seatbelts and gauge faces in matching or complementary colors, sport seats and bodywork upgrades, leathers and interior finishes (aluminum, carbon, wood), choose from multiple steering wheels, add chassis controls and larger wheels, painted wheels and crest logos, get laminated side glass or four-zone climate control, plus more generic items like park warning sensors, a tow hitch and keyless open and start.

Porsche options can be pricey ($750 for XM radio) and unending.Even without using any exclusive factory customizing options, which are virtually limitless, it's none-too-difficult to add a third of the base price in options or run a $60,000 Cayenne S into six digits.

Safety features on all models include electronic stability control, traction control, antilock brakes with off-road capability, trailer stability control, and full-time four-wheel drive.Six airbags come standard: dual-stage front and side-impact airbags for front passengers, and curtain-style head protection airbags on both sides of the cabin.All five seating positions have three-point belts with pretensioners to instantly tighten them and limit stretching on impact.The front belts also have automatic force limiters, reducing potential for belt-related injuries.

Cayenne is easily identifiable as a Porsche with headlights and grille that resemble that of the 911 and Boxster.From the driver's seat, the valley between the headlights looks similar, only wider.The more powerful models have functional design cues indicating higher levels of performance.The GTS and Turbos are distinguished by larger grilles that increase the amount of air flowing through the coolers and the Turbos have strakes along the hood.

The Cayenne is not small, measuring nearly 189 inches in length, with a wheelbase of 112.4 inches.That's about the same length as the current BMW X5, X6 (191.1 inches), and Mercedes M-Class (188.5 inches).Cayenne is also similar to its German rivals in width and height.

In size, Cayenne most closely matches Volkswagen's Touareg, which is no surprise given the two vehicles were developed jointly.Engines and other Cayenne components are built by Porsche in Zuffenhausen, Germany, and mated to the Cayenne at an assembly plant in Leipzig.Cayenne, Touareg, and the Audi Q7 share basic structures, though the Audi is stretched for three-row passenger space.Engine and suspension tuning, styling and all the finish work were the separate responsibility of each manufacturer and in many cases only 15 percent of parts are common.

The Cayenne offers near optimal front/rear weight distribution of 52/48 percent, for outstanding handling balance in all circumstances; the weight in most SUVs is more heavily biased toward the front.At least as important, in Porsche's view, is the Cayenne's optimal aerodynamic balance.Aerodynamic downforce on the rear wheels increases with speed, delivering the high-speed stability that has become a Porsche trademark.

Cayenne's instrument cluster is tucked under a single, prominent arch, with two big gauges on either side of a central multifunction display, tachometer on the left, speedometer on the right, numbered oil temp, coolant temp, fuel and volts surrounding them and styled to look like a 911.The central display presents information on audio and trip functions, mechanical operations and ambient conditions.Cruise control and the switch for the wipers are located on stalks on either side of the steering column.The bulk of the switches, including audio and climate controls, are racked in the center of the dash above the center console.These are replaced with a CRT monitor on Cayennes equipped with Porsche Communications Management, with plenty of small white-on-black switches to amuse you.A dozen vents throughout the cabin distribute warm or cool air evenly.Big, wide outside mirrors offer good rearward visibility.The steering wheel tilts and telescopes to help ensure a proper driving position.

The Cayenne is not as richly appointed as a similarly priced Range Rover Sport, but it's not supposed to be.The emphasis here is sporting flair and German efficiency rather than traditional luxury.(We like both vehicles for different reasons.) We liked the contrasting stitching on the Porsche seats.The standard leather upholstery is high grade, while the standard metal trim has a brushed finish; on premium models what looks like aluminum is aluminum.The front seats stand out for their balance of support, comfort and adjustment range; the sport seats in the GTS yet a notch or two better because of the low-slip Alcantara centers and deeper side bolsters.

The navigation display screen is sizable and mostly out of sun glare.Called Porsche Communications Management, the navigation system comes with a 6.5-inch display and calculates routes and makes adjustments very quickly.It uses DVDs rather than CDs, allowing for maps for the entire United States on a single disk, rather than several that must be changed from region to region.An optional electronic logbook automatically records the mileage, journey length, date and time, starting point and destination address for every trip made.In addition, buyers can opt for a module that will help you find your way back to your starting point, even if the roads or trails aren't on the system's map.Voice recognition and off-road navigation are available options.

Cayenne transports five adults in reasonable comfort.The rear seat is well contoured, with excellent headroom and decent legroom, even when the front seats are well back in their travel range; by virtue of its heavily bolstered outboard seats the center of the GTS rear is best reserved for kids or their child safety seats.The rear floor angles up slightly toward the front creating a very mild footrest that eases leg fatigue.Seating for five is something we're not used to seeing in a Porsche, but don't expect the interior volume of a Lincoln Navigator and don't look for a third-row seat because it isn't available.

The rear cushions lift and the seatbacks fold forward in a 60/40 split, and includes a pass-though slot with a ski sack, allowing Cayenne to haul longer, narrow items inside without flattening or messing up the rear seat.Four D-rings and a cargo net keeps grocery bags and other items from sliding around during travel and a retractable shade-type cover opens and closes over the cargo hold.The cargo area is nicely finished in heavy carpet and the cover is mounted high to preserve maximum concealed storage.

Cargo capacity is nearly 62 cubic feet with the rear seats folded down, and nearly 19 cubic feet with the rear seats in place.The tailgate is two-stage, so either the glass or entire gate can be opened upward, and the electronic latch lets you simply lower the gate to the latch while the electric mechanism pulls it shut; the upgraded power hatch require just a button push.The dimensions of the tailgate opening and load floor allow Cayenne to haul small appliances such as a bar-size refrigerator or a large TV set.With a payload of 1600 pounds, the Cayenne can haul just about anything that'll fit inside without worrying too much about exceeding recommended weights.

In addition to a conventional moonroof you can also order a Panorama Roof comprising four glass panels, three of which slide open under electric power.The massive glass section can be opened either above the first row of seats, the second row, or both rows.A power sunblind is integrated into the roof.

The Porsche of SUVs is what those familiar with the brand probably expect from the Cayenne.One can hear silky mechanical whirring and if you pay close attention, you can feel most of the mechanical components working, each doing its own job, yet it all blends together in a smooth, synchronous whole.The Cayenne is fast, satisfying and, even in the things it does least efficiently, quite competent.It stops with more energy and precision that any SUV we can name.

The deep rumble of the exhaust is a reminder you're driving a Porsche, as is the engine notes of fine mechanisms.Even at idle, the burble of low-restriction mufflers, the cams and the suck of intake air remind us of the late, great Porsche 928, a V8-powered GT that swallowed chunks of pavement at an alarming rate.This is not your typical SUV, though it can perform the duties of one.

Off-road capabilities are considerable.Cayenne invokes images of the Paris-Dakar Porsche 959s.Bigger wheels equals smaller sidewalls and in the end the tires and low-lying bodywork will be the limiting factors; a standard Cayenne V6 is the best for real off-road use and nothing more than a smoothly graded dirt road or sandy beach should be attempted in a GTS or Turbo S.

We drove a Cayenne S hard on a gravel road, a 2.0-mile special stage at Continental Tire's Uvalde Proving Grounds west of San Antonio and were impressed with the predictable handling.Hurling the Cayenne deep into gravel corners well past grip limits was met by the system catching the car mid-corner, allowing us to accelerate hard out of the turn and shoot down another short straightaway and dive into the next turn.With so much technology helping us control the car we would have had to work at it to bite the ditch.In short, the Cayenne works phenomenally well on dirt and gravel roads and make its driver look like a hero.

We drove a Cayenne through a muddy off-road course in Spain.This was not a boulder-laden wilderness trail like the Rubicon, but included axle-deep mud and long, steep, low-grip grades.Up, down and across, the Cayenne performed flawlessly.In most cases the onboard electronics did the heavy lifting, and the driver had to simply, lightly, modulate the throttle or brake in low range.When introduced, Cayenne's back country performance impressed even the jaded, and it supported Porsche's assertion that it has more off-road capability than the BMW X5, X6, or Mercedes M-Class, which we've driven in similar conditions.Cayenne has a maximum ground clearance of 8.5 inches, or 10.6 inches with the optional air suspension.It can ford 19 inches of water, nearly 22 inches in the off-road mode with air suspension.The Advanced Off Road Package adds skid plates to protect the underbody and a locking rear differential.We drove a Turbo with these options on the desert sands of Dubai and were astounded by the vehicle's prowess in difficult conditions.

Cayenne's permanent all-wheel-drive system, with its variable-rate center differential managed by multiple clutch plates, is similar to that used on all-wheel-drive versions of the Porsche 911.Cayenne enhances this setup with a low-range set of gears along with a locking center differential for creeping over rugged terrain.The all-wheel-drive system can vary the amount of engine power distributed to the front and rear wheels, sending more or less power in one direction depending on available traction and other conditions.The Cayenne has a default power split of 38 percent front, 62 percent rear, but is said to be capable of 100 percent to either end; we'd be very careful with the gas pedal in such conditions.The nominal drive is biased much a bit more to the rear than most SUVs, more closely replicating the rear-wheel-drive characteristics of a sports car.

On the road, the Cayenne handles crisply, but it's no Carrera.Though lighter than the BMW X5 and X6, the lightest Cayenne tips the scales around 4,775 pounds, the S about 4,950 pounds and the Turbo about 5,200 pounds (and more than 5,700 pounds when fully optioned).All this weight rears its head in transient maneuvers.Cayenne performs lane-change maneuvers better than an SUV, but there's no getting around the physics of all that mass when pushed hard in tight cornering situations.That said, the Cayenne offers excellent grip in steady state corners, even slippery corners.Steady corners can be taken quite quickly.The fat Michelin sport tires on the GTS models will prove the value of larger seat bolsters due to the grip they offer.

Porsche Dynamic Chassis Control features active anti-roll bars that almost eliminate body roll (lean) in corners; PDCC cars can be identified by looking inside for the silver chassis controls behind the shifter.This system makes it easier to control the car when driving hard through corners, improving cornering stability, and the choices in ride softness let you cruise or hurry as wished; the Normal mode is almost as smooth as the Comfort mode and an excellent default position.Porsche Stability Management was upgraded for 2008 with pre-loading of the brake system when needed and a trailer stability control algorithm added to improve stability when towing.

The V6 in the standard Cayenne is a narrow-angle 3.6-liter V6 with a single cylinder head and uses Direct Fuel Injection.It produces 290 horsepower at 6200 rpm and 273 pound-feet of torque at 3000 rpm.

We found the V6 enjoyable to drive and welcomed the midrange increase.It's available with a six-speed manual transmission, which is equipped with a feature called Porsche Drive-Off Assistant that allows a driver to easily set the Cayenne in motion on steep grades; the system automatically maintains brake pressure when the brake pedal is released, then releases the brakes once the driver begins to let out the clutch pedal.The manual's shift action is sweet, agricultural by Porsche car standards but very good by truck standards.The V6 Cayenne delivers adequate acceleration performance.Porsche reports 0-60 mph times of 7.5 seconds and a top speed of 141 mph.Its wide power band gets the Cayenne up to speed in convincing fashion, and the V6 is the lightest Cayenne.

The 4.8-liter V8 in the Cayenne S generates 385 hp at 6200 rpm and 369 pound-feet of torque at 3500.This engine produces 405 hp at 6500 rpm in the GTS by virtue of better breathing and increased engine speed.The V8s are pure Porsche with the latest technology and materials, including a dry-sump lubrication system that allows uninterrupted oiling at extreme angles of operation, either off road or at high lateral loads when cornering at speed on pavement.

We found the Cayenne S offers responsive performance.Porsche says it can accelerate from 0-60 mph in 7.9 seconds.At any speed, the six-speed Tiptronic S automatic kicks down quickly with a jab at the gas pedal and the Cayenne S accelerates like a jumbo jet approaching rotation speed.We're not sure why anyone needs more get-up in a big SUV than the Cayenne S offers, but we're well beyond need here and it's not a bad place to be.

The Cayenne GTS has shorter gearing than the Cayenne S in addition to its 20-hp advantage, giving it quicker acceleration performance.Porsche says the GTS covers 0-60 mph in 5.7 seconds with the manual transmission, 6.1 seconds with the six-speed automatic.A GTS with the manual is revving higher when cruising in top gear at normal highway speeds (70 mph is about 2800 rpm, typically 2000 rpm in the average SUV).Yet the manual allows the best control and flexibility.We found on some tight uphill hairpins the traction control intervened to eliminate some tire spin but choosing a gear higher and flooring the throttle made better progress; that would be hard to do with an automatic.

The Cayenne Turbo generates 500 horsepower at 6000 rpm and 516 pound-feet of torque between 2250 and 4500 rpm.The Turbo can accelerate from 0-60 mph in just 4.9 seconds and from 0-100 mph in just over 12 seconds, which we experienced at the Uvalde Proving Grounds.The Turbo hit its top speed of 171 mph there.

The Turbo S proves the old adage that higher speeds require exponentially more money as the extra $26,000 above a regular Turbo adds 50 hp and about 40 lb-ft of torque to take 0.2 seconds off the 0-60 dash and top speed is up by 3 to 174 mph.Sure, it's a bragging rights thing in the limited U.S., but sending a postcard to the Hemi Challenger at a dragstrip is silly fun.

Brakes, traditionally a Porsche strong point, are appropriate for the brand.The Cayenne brakes feature six-piston fixed calipers on the front wheels and four-piston calipers at the rear.Vented brake discs measure 13.0 inches on all V6 Cayennes with calipers finished in black.The Cayenne S and GTS get even larger 13.8-inch front discs and silver-painted calipers.The Cayenne Turbo gets even larger discs, 14.5 inches in front and 14.1 inches at the rear with red calipers.ABS programming is adapted to four-wheel drive use by allowing some wheel lock to build a wedge in front of the tire and stop shorter, a great feature on gravel roads.

Composite ceramic brakes are on the Turbo S (and represent a significant part of the price increase).These excel at shedding heat and the discs will reportedly last the life of the car, but they are also lighter which helps improve steering response, handling, and ride due to lower unsprung weight.

On pavement, the Cayenne is smooth, fast, and big.It's not just acceleration or the top speed that impressed us, but the high speeds the Cayenne comfortably carries in most circumstances.The steering isn't as quick as that in a 911, but its weight and response have a familiar feel.The air suspension keeps it on the stiff side, though it can be manually softened if the driver chooses.It's impressively precise and responsive given its 2.5-ton mass.The Cayenne drives lighter than other big SUVs, including the X5, X6, and M-Class, and speed creep is a constant issue.Almost without realizing it, you can be traveling 120 mph on roads posted 65.Oops.And 80 mph feels like comfortable cruising, officer.

The towing capacity of the Cayenne is impressive.All models are rated to tow just over 7700 pounds.That's plenty to pull that vintage 356 around.

Fuel economy is not the strongest asset of the Porsche Cayenne due to its considerable weight and performance orientation.However, stepping up or down in horsepower does not drastically affect fuel economy nor does switching transmissions.The 2009 Cayenne is rated 14/20 mpg (manual or Tiptronic); Cayenne S rates 13/19 mpg; GTS 11/17 mpg with the manual, 13/18 with Tiptronic; Cayenne Turbo and Turbo S get 12/19 mpg.All call for 91 octane fuel.SUVs are not subject to the Gas Guzzler Tax.

By comparison, the Cayenne Turbo gets slightly better fuel economy than does the big-power Mercedes-Benz ML63 (11/15 mpg).Most competitors have similar ratings: BMW X5 and X6 six-cylinder (15/21 mpg) and V8 (12/18 mpg), Touareg V8 (13/18 mpg) and Mercedes ML350 six-cylinder gas (15/20 mpg).Only the Mercedes ML320 diesel (18/24 mpg) and upcoming and not-yet-tested BMW X5 diesel will offer Cayenne V8 torque and notably better mileage.

NewCarTestDrive.com editor Mitch McCullough reported from Texas, with J.P.Vettraino reporting from Detroit, Greg Brown from Dubai, and G.R.Whale from Los Angeles.