For a company that once eschewed the V6 as the lesser of all six-cylinder formats and not befitting its upper-crust heritage, Porsche's lineup is sure chockablock with six-piston engines arranged in some form of V. To be more specific, there are four and, if you'll please forgive me for jargoning up the very first paragraph of this story with technological gobbledegook, they are: A) a narrow-angle - 10.6 degrees to be exact - 3.6L sourced from Volkswagen that is the Cayenne's new base powerplant.
B) a 90-degree 3.6L that is the new base engine in the 2011 Panamera. C) a 60-degree supercharged V6 liberated from the Audi S4 that makes up the gasoline portion of the new Cayenne Hybrid's powertrain. D) a 60-degree 3.6L turbodiesel sourced from Audi that powers the 2011 Cayenne and is the first diesel in a Porsche vehicle since the company stopped making farm tractors. A and B, though vastly different powerplants, share exactly the same power specifications - 300hp and 400Nm of torque. C is being heralded by Porsche as an alternative to its base 4.8L V8 with almost as much power - 380hp when the petrol and electric motors are combined - but reduced fuel economy, 8.L/100km overall. And D has been certified for use in Audi's North American version of its Q7, but is not homologated for use in the Porsche there, so it may not be available Stateside in the short term. But it will, according to Porsche Middle East, come to the Gulf region, despite the lack of popularity here for anything diesel-powered.
The diesel - choice D, that is - is, by far, the best of all the Cayenne V6s. In fact, it may be the best powertrain available for any Cayenne, regardless of displacement, number of cylinders or horsepower. The V8s may get all the glory, the hybrid more headlines and the newly fortified 3.6L V6 the lowest price, but it's the diesel that's ultimately more satisfying. For instance, though its official specification - 7.8 seconds to 100 kilometres an hour - places it at the hind end of the Cayenne lineup, it just doesn't feel that way at all. Acceleration from a standstill is brisk and passing on the highway is truly quick. Indeed, at times, the Cayenne diesel felt sportier than the Panamera V6 I recently tested, even though the big sport brute outweighs the sedan by more than 300kg.
Not only that, it's super smooth, actually feeling more sophisticated than the petrol-fuelled 3.6L in the base model - having a diesel engine quieter, smoother and more sophisticated than its direct petrol counterpart is not common. You would be a fool not to appreciate the diesel's phenomenal fuel mileage that, thanks to now incorporating Porsche's unique auto start-stop function, is rated at a truly frugal 7.4L/100km. That's truly incredible fuel economy for an SUV weighing significantly more than two tonnes. By comparison, the hybrid manages but 8.2 L/100km and the base V6 9.9L/100km (while the 4.8L turbo V8 sucks back 11.5L over the same distance). And remember that hybrids almost never match their rated fuel economies in real-life driving, while diesels do. Throw in the fact that the hybrid will have a base price of Dh308,900 while the diesel starts at just Dh247,600, and the sense behind the more complex petrol/electric powertrain evaporates.
The diesel's performance is helped by two changes to the new Cayenne. First, Porsche's big sport-ute has lost as much as 185kg of weight thanks to incorporating more high-strength steel, the loss of the low-range set of gears and the use of aluminium in the doors. More importantly, the Cayenne uses a new eight-speed Tiptronic automatic transmission. The added set of gear ratios not only means less drop in engine revs between gears but it also masks the diesel's relative lack of top-end horsepower; while the turbodiesel boasts a whopping 550Nm of torque as low as 2,000 rpm, it generates only 240hp at 4,000 revs. The new petrol-fed 3.6L V6 is, by comparison, not nearly as frugal or as confident. Though Porsche says that it accelerates to 100kph in the same 7.8 seconds as the diesel and has a slightly higher top speed, its relative lack of torque means that comparative highway passing acceleration requires two downshifts where the diesel needs but one and sometimes none at all.
However, one shouldn't get the idea that the base V6 isn't competent. It is miles ahead of the old 3.2L, which was seriously slow. It is just that the diesel is the much superior V6 and more cost-effective than the hybrid. The base V6 will start at Dh233,000; that makes the diesel's price seem like a bargain. All the more reason why it's the best of the Cayennes. But given the inconvenience of using diesel, will people here in the UAE want one? It is more difficult to find a diesel pump, the fuel costs more than petrol and its quality is suspect from station to station. Porsche says it will counter this last bit with more frequent service intervals; but it will be interesting to see what kind of sales the diesels, no matter how good they may be, will have.