Porsche Doppelkupplung Transmission (PDK)

Porsche Doppelkupplung transmission (PDK)

This technical description covers the design and operating principle of the 7-speed dual-clutch transmission, called PDK (Porsche DoppelKupplung) at Porsche. Since this transmission is used in several different Porsche models, only the basic functions will be described here.

Introduction

Porsche has worked with Doppelkupplung transmissions since the '70s.
The first racing car with PDK was used in 1984 in the Porsche 956 at Nurburgring, while Porsche had its first big win with a PDK transmission in 1986 with the enhanced 962 in Monza. The main advantage over rival vehicles was that gearshifts could be accomplished without interrupting tractive power. This allowed shorter shifting times with significantly improved acceleration for the racing car. This type of transmission proved successful during the highly challenging long-distance World Championships, although two dry clutches were used. The high level of lining wear associated with this type of clutch was not an issue since the clutch plates would be replaced immediately after each race.

Standard development was not followed up at that time as control electronics systems and computer capacities in the '80s were not yet sophisticated enough to perform the complex control functions that were essential to meet the comfort requirements for road vehicles. Also, the mechanical control elements for precise hydraulic valve control were not yet fully developed or financially viable at that time.