The Porsche Cayenne is the rally car of big, heavy SUVs. It drives like a big sports car. Measured against other SUVs, it's hot. Measured against sports cars, it's quick and it's fast. Handling and stopping are impressive given its mass, but there's no denying that mass. And therefore, the Cayenne is no alternative to a Carrera: For true sports car performance, there is no substitute for the Porsche , except perhaps the . But among SUVs, the Cayenne hauls. It is the Porsche of its class.

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 Porsche 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 , 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. The Porsche Cayenne invokes images of the Paris-Dakar . 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 Porsche 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 makes its driver look like a hero.

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 . 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 Porsche Cayenne handles crisply, but it's no Carrera. Though lighter than the and , the lightest Cayenne tips the scales around 4,750 pounds, the Cayenne 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 any other 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 6,200 rpm and 273 pound-feet of torque at 3,000 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 Cayenne V6 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 6,200 rpm and 369 pound-feet of torque at 3,500. This engine produces 405 hp at 6,500 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 Porsche Cayenne S offers responsive performance. Porsche says it can accelerate from 0-60 mph in 6.4 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 Porsche 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 Cayenne GTS with the manual is revving higher when cruising in top gear at normal highway speeds (70 mph is about 2,800 rpm, typically 2,000 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 Porsche Cayenne Turbo generates 500 horsepower at 6,000 rpm and 516 pound-feet of torque between 2,250 and 4,500 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 0.1 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 at a dragstrip is silly fun.

Brakes, traditionally a Porsche strong point, are appropriate for the brand. The Porsche 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 Porsche 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 Porsche Cayenne drives lighter than other big SUVs, including the X5, X6, and , 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 Porsche Cayenne is impressive. All models are rated to tow just over 7,700 pounds. That's plenty to pull that vintage 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 Porsche 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), 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.