With the introduction of the new 911 Targa later this year, Porsche is completing the fastest ever generation change in the 911 series. Two new power units with Direct Fuel Injection (DFI) improve both the performance and economy of the car, the fast-shifting Porsche Doppelkupplungsgetriebe (PDK) - or double-clutch transmission - replaces the optional Tiptronic S automatic transmission, and electronically-controlled Porsche Traction Management (PTM) takes the place of the former viscous-coupling all-wheel drive system.
The latest addition to the new generation 911 line-up comes in two variants; 911 Targa 4 and 911 Targa 4S. The Targa 4 version is powered by a 3.6-liter flat-six engine that develops 345hp and gives the car a top speed of 176mph. The Targa 4S displaces 3.8-liters, develops 385hp, and accelerates to 185mph.
The visual highlight of the 911 Targa remains the distinctive glass roof made up of two segments; the elegant sliding roof above the occupants and the versatile top-hinged tailgate. When opened completely, the roof slides beneath the tailgate within 7sec to offer open space above the passenger compartment. The sliding roof comes as standard with a new electrically-controlled sun-blind, which offers bette shade than before. When closed, it spans the entire area of the sliding roof, and can be opened and closed independently of the roof itself.
The glass roof and the tailgate are manufactured from specially-treated glass designed to deflect the sun's glare, thereby protecting the occupants even in bright sunshine from UV radiation and excessive heat. As the designation implies, the 911 Targa 4 and Targa 4S remain exclusively available with four-wheel drive. For the new generation models, the all-wheel drive is now provided via electronically-controlled Porsche Traction Management (PTM), which replaces the viscous multiple-plate clutch fitted previously. The superior PTM system was first developed for the 911 Turbo and has been modified for the Targa models. The transmission delivers an even higher level of driving stability, traction and agility, further enhanced by the mechanical limited-slip differential also now fitted as standard.
PTM feeds exactly the right amount of torque through an electronically-controlled multi-plate clutch to the front wheels, supplementing the flow of power to the rear wheels. Combined with the highly dynamic PTM control system, this clutch distributes power and torque to the axles as road and driving conditions change. With the previous viscous clutch, up to 40% of torque could be directed to the front axle. In contrast, the PTM system delivers an infinitely variable torque split, and is able to distribute up to 100% of traction to the front or rear wheels.
PTM provides a faster and more precise transmission of power in all driving situations, and this offers not only excellent stability at high speeds, but also increases the level of responsiveness.