The 2009 Porsche Cayenne is offered in five different models--the base V6, the S, the GTS, the Turbo and the Turbo S--each offered with a different powertrain. A 290-horsepower, 3.6L V6 comes with the base model, paired with either a standard six-speed manual or six-speed Tiptronic S automatic transmission. The S utilizes a 385-horsepower, 4.8L V8, and is available only with Tiptronic S transmission. The GTS squeezes 405 horsepower from the 4.8, with the six-speed manual as standard and Tiptronic S available. The Turbo and Turbo S make use of the 4.8 as well, but it's fed by twin turbochargers. The Turbo's engine makes 500 horsepower, while the Turbo S churns out 550. All Cayenne engines feature direct injection for improvements in both fuel efficiency and power. All V8 models adopt VarioCam Plus variable valve timing, which varies intake valve timing and lift, and a new variable oil pump for the dry-sump lubrication system that is oriented toward high-performance driving. The five-passenger Cayenne offers two spacious rows of seating; the rear seat is split 60/40 and can fold flat to expand the cargo floor for larger items. The Cayenne adapts to changing road conditions using Porsche Dynamic Chassis Control (PDDC), which utilizes hydraulic pressure to change the stabilizer-bar response depending on the road surface or cornering forces. The system allows both a smooth ride when on or off-road. All Cayenne models get large disc brakes with six-piston calipers in front and four-piston units in back. Turbo S models benefit from especially grippy ceramic composite brakes. The Porsche Stability Management system--including a trailer stability control mode--is standard across the line, as is a power liftgate and "Sport" mode, which changes the engine mapping when engaged for improved throttle response. When properly equipped, the Cayenne can tow over 7,700 pounds. The options list for the Cayenne is vast, including everything from an off-road package with skid plates to a trailer-towing package, luxury features such as a heated steering wheel and various distinctive woodgrain interior trims. Base V6 models get 17-inch alloy wheels, while S models upgrade to larger 18-inch wheels. Several different wheel designs are optional, ranging up to flashy 21-inchers, which are standard on Turbo S models.