First of all, let's review Bruce Anderson's quote about the problems of the manual transmission cars versus tiptronic transmission cars before going on to the subject of
PDK
:
So, the concern question: is the PDK flywheel and 2 clutch assembly even heavier than the manual transmission one? The following picture is a cut-out of the DSG (same thing as PDK). You can see how thick the flywheel and 2-clutch assembly is (but diameter is smaller though):
No worries. The chain drive on the tail end of the crankshaft will be gone (DFI): :banana:
Weight down, stability up – the engine block
Despite their more sophisticated and complex technology, the new power units are approximately six kilos lighter than before. A two-piece crankcase with integrated crankshaft bearings is perhaps the most significant change in technology, replacing the former four-piece block with its separate crankshaft bearing housing. The advantage is not only a reduction of weight, but also a smaller number of individual components. At the same time Porsche’s engineers have enhanced the thermal and mechanical stability of the engine, making it even more robust by converting the design and configuration of the cylinders from open- to a closed-deck layout.
This means that the cylinder liners so far freely exposed around the cylinder gaskets are now connected with the housing by a top plate comprising the coolant sleeves. In particular, this helps to give the cylinders even greater stability in their shape and design, always remaining perfectly round. Two further advantages are the reduction of oil consumption and, thanks to less friction, even greater fuel economy.
Fewer moving parts – new timing chain drive
The new engines no longer require the former intermediate shaft serving to drive the timing chains. Originally this shaft had the task to reduce the loads acting on the camshaft drive.
Now, through the use of new, highly resistant timing chains, there is no longer a need for such an intermediate shaft, moving masses and the weight of the engine being reduced accordingly.
The
Cayman
/
Boxster
/
911
have been using the same engine design since 1997. The exception being the Turbo,
GT3
,
GT3
RS and GT2.
Porsche
has re-designed the engine for MY09 on the
911
. The new engine is not supposed to suffer from RMS, as they specifically handled this problem. I don't think
Porsche
will keep producing two different engine types for the
911
/
Cayman
/
Boxster
, most likely these new engines will find their way into the
Cayman
/
Boxster
.
#1 QUOTE- No worries. The chain drive on the tail end of the crankshaft is now long gone:
#2 QUOTE
Help please? Quote #1 says problem solved long ago? Looks like Quote #2 says problem will be solved. could someone explain this a bit more?
The new engine block and engine design "should" get rid of the old RMS problem.
Additionally I spoke to
Porsche
today at Parade in length about the
PDK
and it weighs between the weight of a manual and a tiptronic. Walter Rohl says he cannot shift a manual as fast at the
PDK
.
Does the new engine/engine block have a name? Or is it just the engine with the new Direct Injection?
I dunno, will ask if I get a chance...
I thought the new (987 vs the
986
) engines had the extra bearing journal to keep the crankshaft supported. I remember reading this somewhere in a
boxster
buyers guide type article?
