^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ما شاء الله البورش اليديده 911 توربو تسارعاتها تحطيم لكل سيارات ال 500 حصان
شكله ال PDK لعب دور كبير لانه افضل جير لحد الحين والسبب انه الجير الوحيد اللي يستحمل عزم عالي بدورات منخفضة مع الدبل كلتش
هاي التسارعات الصاروخيه تدل على ان البورش توربو ما تخسر احصنة على الداينو والفضل الى PDK gearbox
على فكرة ترى جير ال PDK بورش صنعته مع ZF افضل شركة جيور
Porsche
Porsche AG offers a series production
[36] of two new longitudinally-installed,
ZF Friedrichshafen AG designed and built with Porsche
[37][40] '7DT' wet-clutch versions
[36] of its previously
race-only
[5][40] Porsche Doppelkupplungsgetriebe
[40] (PDK) transmission.
The first variant, the 7DT-45,
[36] is used on its 2009 997 Carrera and Carrera S models.
[3][37][68][69] This version is also offered on the 2009 Cayman,
[3][36] Boxster
[3][36] It uses a
ZF Sachs ND2015 clutch pack,
[36] and has a torque handling capacity of 500 N·m (369 ft·lbf).
[36] A higher torque version of the same transmission, the 7DT-70,
[36] is also available for the 2010 911 Turbo.
[36][70] This is rated at 780 N·m (575 ft·lbf),
[36] and uses a different ZF Sachs clutch - the ND2216.
[36]
The second PDK variant, the 7DT-75,
[36] is available on the 2009 Panamera.
[3][36][40][71] This is constructed fundamentally different to the 7DT-45/7DT-70 versions; in that the internal shafts are mounted above the input shaft, so as to achieve a lower centre of gravity for the Panamera.
[36] It also uses just one oil circuit,
[36] whereas the 7DT-45/7DT-70 use two separate circuits;
[36] with very different specifications of fluids needed.
[36]
Both fundamental variants use seven forward speeds,
[3][38][68] and Porsche claim the Doppelkupplung PDK transmission will replace the outgoing conventional
Tiptronic automatic transmissions.
[37][68] However, other reliable industry sources state that Porsche still intends to use conventional automatics; with the eight-speed
ZF 8HP being cited.
[36] Like all DCTs, the Porsche PDK transmission is fundamentally two separate manual transmissions in one.
[3] With the 1st, 3rd, 5th, and 7th gears and reverse available on one shaft,
[3] and 2nd, 4th, and 6th gears available on the other shaft.
[3][72]
Porsche claim noteworthy improvements in CO2 emissions of around 15% when comparing DCT installations against its former automatic transmission,
[36] of which a half can be directly attributed to the DCT.
[36] And when compared directly with a manual transmission; 16% improvement can be directly attributed to the DCT.
[
وهذا هو المصدر:
http://en.wikipedia.org/wiki/Dual_clutch_transmission
