Volkswagen and Porsche rolled out the second iteration of their jointly developed crossover SUVs in New York, making it the world debut of the Porsche Cayenne in all of its variations as well as the world debut of the hybrid-electric version of the Volkswagen Touareg.
Both vehicles’ exterior styling is evolutionary from the companies’ original models, with some influence of more recently introduced models’ styling themes. But while they look quite similar to their predecessors, both new crossovers enjoy significant improvements under that new sheetmetal.
Most significantly, increased use of high-strength steel and aluminum has contributed to the elimination of an incredible 400 lb (181 kg) of mass from the previous models. “We looked at both alternative materials and alternative constructions,” reported Martin Bratzler, Porsche’s Cayenne Product Manager.
Use of aluminum chassis parts contributed to a reduction of the weight of the chassis by 145 lb (66 kg), while aluminum fenders and rear hatch contributed more weight savings along with the use of a new lighter-weight all-wheel-drive system. “You won’t find 400 lb in one area of the car,” Bratzler said. “You have to look at each part.”
The Cayenne comes to America with a 300-hp (224-kW) 3.6-L direct-injected gasoline V6 as its base engine, with an available 400-hp (298-kW) 4.6-L direct-injected gas V8 and a 500-hp (373-kW) twin-turbo gasoline V8 as options.
The Cayenne and Touareg hybrids share their hardware, with each company calibrating its software to suit its vehicle. “The software is probably the most distinguishing factor between the cars,” said Bratzler. “The challenge is bringing out the characteristics of the car.”
For Volkswagen the characteristic the company wanted to highlight was luxury, so VW engineers spent extra time working on programming the clutch that engages and disengages the electric motor so that it would be unobtrusive, said Bernd Stiebels, Project Manager for the Touareg’s hybrid drivetrain.
“The most difficult challenge was to get the transitions on a very high comfort level,” he said. The problem is that the clutch’s friction point is not always the same; it varies depending upon use. The VW model's clutch responds differently in a variety of circumstances with the goal of accurately predicting its action in use for the smoothest possible engagement and disengagement. “We are constantly learning the point where the clutch delivers the torque of the engine,” he said.
The hybrid’s supercharged, direct-injected V6 engine produces 333 hp (248 kW) according to Porsche. Total system power for the Touareg is 375 hp (280 kW), while the Cayenne is rated at 380 hp (283 kW).
Both vehicles use an Aisin eight-speed automatic transmission, which the companies say is preferred by their customers over the CVT commonly seen in hybrids. The parallel-hybrid design permits the gasoline engine to be decoupled and shut off when coasting at highway speeds. The layout also lets the gasoline engine put power to the road without assistance from the electric motor, which is why the vehicles enjoy a 7700-lb tow rating, which is higher than that of General Motors’ hybrid pickup trucks.
The Sanyo-supplied 288-V nickel/metal-hydride battery pack resides beneath the luggage compartment, providing power to the 35-kW, 295 lb·ft (365-N·m) Bosch electric motor through Bosch power electronics.