The Prius of Porsche – A less guilty pleasure

With total sales approaching some 300,000 units sold so far, the Porsche Cayenne is the company’s best-selling model ever. Sales of Cayenne have generated huge amounts of cash for the venerable German auto manufacturer, allowing them to expand safely into new territory with more 911 and Boxster variants, the Cayman sports car and the Panamera luxury sedan.

For the 2011 model year we get a redesigned Cayenne, inside and out, which includes a first-ever hybrid powertrain. Showing the breadth of choices, buyers can spend from just under $50,000 to just over $100,000.

The Cayenne hybrid tested here is the first full-hybrid system that Porsche has put in a vehicle. The Panamera had a start-stop system, but this is a true hybrid.

At first glance, you’d swear the Cayenne had been downsized for 2011, though it’s actually two inches longer, and rides on a wheelbase 1.6 inches longer. What isn’t an illusion is the Porsche’s new, svelte weight loss, and salutary effects on performance and fuel economy. The Cayenne is 400 pounds lighter than the last model; one of the biggest drops I’ve seen in a redesign, but still weighs a ton (2.5 tons to be exact). It also adds back the fat that was trimmed from the lineup at large; this due to the battery pack fitted below the cargo floor (where the spare tire fits in other models). At 4,938 pounds, the Hybrid is 400 more than the V-8.

Porsche saved 73 pounds by omitting the low-range gearbox (handy for off-road use, but superfluous elsewhere); lightened the chassis and body panels; and relied more on aluminum and plastic composites.

The Cayenne does appear more Porsche-like than the original design, which was a serious compromise between SUV proportions and a Porsche’s inherent trimness. While changes are nuanced, this design flows better, especially on the hood, where both the high side wings and the size and position of the headlights mimic the iconic 911. The horizontal grill looks less off-road burly. Even the shape of the roof and the camber of the rear glass resemble a coupe.

What’s more interesting to me is the completely new interior. Upgrades include a gorgeous stitched-leather interior, polished aluminum fittings throughout, and a spectacular banked center console, inspired by its sibling, the Panamera. The mood inside is smart, distinctive, and swirls with good looks from every angle. The Cayenne is built to an impeccable fit and finish; resonating with an interior rich enough to leave residents at the Cloisters in Sea Island green with envy.

For 2011 the Cayenne comes in four flavors: the Cayenne ($47,700) and Cayenne S Hybrid ($67,700) both have V6 gas engines; the Cayenne S ($64,400) and Cayenne Turbo ($106,000) both have 4.8-liter V8 engines; rated at 400 and 500 hp, respectively.

The Hybrid produces 380 horsepower by joining an S4 Audi 3.0-liter 333-horsepower supercharged 324-pound-foot V-6 with a 47-horsepower 295-pound-foot electric motor supercharged V-6, electric motor and nickel-metal-hydride batteries. This is the identical hybrid system and Cayenne platform that underpins the new Volkswagen Touareg Hybrid.

Most high-performance hybrids, including BMW’s competing ActiveHybrid X6, have seemed like green window dressing. Adding a hybrid system sends the price shooting up, while mileage and performance barely budge. The Porsche is different. Squeeze the gas, and at just 1,000 r.p.m. — barely above idle — the 47-horse electric motor and 333-horse engine serve up a monumental 428 pound-feet of peak torque. Within 6.1 seconds, you’ve breached the 60 mph barrier; 1.3 seconds quicker than the new Cayenne V-6, and just a half-second behind the V-8.

Because of its full-hybrid architecture, the Cayenne S Hybrid can glide silently along, up to 37 mph, in all-electric, or E-power mode. For short distances or in slow-moving traffic, it seems to be an ethereal version of the big German truck, the Flying Deutsch-man.

What’s really different (and a bit weird) about the Cayenne S Hybrid is that, on the highway, the entire hybrid engine system decouples (shuts off) from the wheels. When this happens, the vehicle coasts, free of mechanical drag, eliminating the engine braking effect. While “sailing” (as Porsche calls it), the Cayenne can operate at speeds up to 97 mph. This significantly raises the highway fuel economy to above 30 mpg; fully 5 mpg better than its previous rating. It was a completely different feeling to be going down the highway at 80 mph and have the Cayenne suddenly go silent.

Another hybrid annoyance — regenerative brakes that cause a dragging sensation every time you lift off the accelerator and press the left pedal — has been fine-tuned. You don’t feel all of the hybrid components working, but you can keep apprised of what’s going on by checking out displays in the gauge cluster and instrument panel.

While it’s doubtful that few Cayennes will ever see much off-roading (we actually didn’t venture beyond blacktop), it does boast as much capability in that venue as a Land Rover. It has a simplified off-road management system, complete with locking differentials in the center and rear.

Driven in haste on twisty canyon roads, such as the Apache Trail outside Tortilla Flats in central Arizona, the Cayenne S Hybrid feels athletic and lively but not exactly eager, and certainly not nimble. You can certainly push the Cayenne to do what’s asked but it does so reluctantly.

As expected for a luxury vehicle, the Cayenne comes with a full complement of safety gear, including front, side and side curtain airbags, with rear side airbags optional. As of this writing, it has not been crash-tested by the Insurance Institute for Highway Safety or the National Highway Transportation Safety Administration.

It will be interesting to see how popular the hybrid Cayenne does over its non-hybrid offerings. Hybrid buyers are much more narrowly focused. Cayenne’s success will require them to seek out the latest vehicle technology, and hopefully, exercise some amount of social responsibility. Buyers of luxury vehicles and luxury SUVs really don’t need to save on gas; rather, they purchase based upon luxury, comfort and status.

Because of ever-restrictive CAFÉ standards imposed by the Federal Government, it won’t be long before you won’t be able to buy any luxury vehicle that isn’t getting significantly improved fuel economy from where they are by today’s standards. To that end, Porsche has already announced that the new Panamera sedan will be the next to undergo the hybrid transformation. This will occur next year, using essentially the same system as the Cayenne S Hybrid.