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Old 09-02-2013, 09:21 AM   #12
sb01box
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Join Date: Dec 2006
Location: Santa Barbara, CA
Posts: 308
Quote:
Originally Posted by Cloudsurfer View Post
The DMFW is there to both dampen harmonics of the crank (the same way that many engines use a harmonic damper on the front crank pulley, while all but the M97 do not) AND to provide some "squish" from driveline shock getting transmitted to the crank (the alternative here being a sprung clutch friction disk).

The latter part of this is why the PDK cars do not need a DMFW. Due to the nature of being computer controlled (i.e. smooth, perfectly rev matched shifts EVERY time) and the fact that there are two clutches, one between the engine and gearbox/ one between the gearbox to the halfshafts, the "squish" factor is not needed.

Now, I'm not sure if the DFI motors are running a harmonic damper on the front crank pulley or not (haven't gotten to play with one of these yet), but I imagine they have to be damping harmonics somewhere.
thanks - yes, my question is the same as your last sentence. "what mechanism, if any does the pdk equipped cars have for engine/trans harmonic dampening; aka DMFW?
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