![]() |
|
|
|
Cars & Coffee Killer
Join Date: Sep 2004
Location: State of Failure
Posts: 32,246
|
What, exactly is a "dual mass flywheel"?
__________________
Some Porsches long ago...then a wankle... 5 liters of VVT fury now -Chris "There is freedom in risk, just as there is oppression in security." |
||
![]() |
|
Registered
Join Date: Nov 2002
Location: Rogue Valley, Oregon
Posts: 1,736
|
Chris,
I'm probably wrong but I think it is a flywheel that amounts to two seperate disks conected together with a flexible union. It is supposed to dampen out gear rattle. Experts? They are quite heavy. Troy
__________________
Troy Past: 1975 911S Silver Anniversary-rebuilt and sublime. Past: 1988 Carrera-backdated with a 3.6 and all the goodies. Present: 2011 GMC 2500HD with the 6.0 & 4x4!, 2004 Toyota Sequoia (wife's) |
||
![]() |
|
Cars & Coffee Killer
Join Date: Sep 2004
Location: State of Failure
Posts: 32,246
|
Thank you, that makes sense in a way.
I'm 99% certain that my 951 does not have a dual-mass flywheel.
__________________
Some Porsches long ago...then a wankle... 5 liters of VVT fury now -Chris "There is freedom in risk, just as there is oppression in security." |
||
![]() |
|
Banned
Join Date: Aug 2005
Location: Carmichael, CA
Posts: 53,593
|
Quote:
|
||
![]() |
|
Writer/Teacher
|
That does sound strange. Off-boost, my 951 is a kitten - very very easy to drive at low speeds (or high speeds, for that matter).
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
Writer/Teacher
|
That is correct. There was actually a Tech article in the newest EXCELLENCE in which a reader asks about performance mods for late-model 911s, including swapping out the dual-mass flywheel for a more conventional unit. The writer advised against it, claiming that the noise from the gearbox will be so overwhelming at any RPM lower than WOT that the car will sound to most like it's broken.
__________________
Current Stable: Black 07 Porsche 987 Cayman S: Long-Tube Headers; FabSpeed Exhaust; VividRacing ECU Tune; IPD Plenum; 997GT3 Throttle Body. Blue 1983 Porsche 928S. 1985.5 Porsche 944 Rat Rod. 2011 Acura MDX. 2008 Mazda 3. Gone But Not Forgotten:Garnet Red 86 Porsche 951("The Purple Pig"). Alpine White 83 Porsche 944 ("Alpine Wolf"). Guards Red 84 Porsche 944. |
||
![]() |
|
![]() |
Registered
Join Date: Nov 2002
Location: Rogue Valley, Oregon
Posts: 1,736
|
I read that too in Excellence. I laughed. My 911 rattles like crazy and until I knew what it was, I was concerned. The better throttle response/quicker revving is worth the extra noise. Frankly, it is only noticable at idle with the car in neutral or at very slow speeds. The light flywheel does make the car more difficult to launch or drive at slow speeds because of the off/on feel (less inertial, I guess).
Troy
__________________
Troy Past: 1975 911S Silver Anniversary-rebuilt and sublime. Past: 1988 Carrera-backdated with a 3.6 and all the goodies. Present: 2011 GMC 2500HD with the 6.0 & 4x4!, 2004 Toyota Sequoia (wife's) |
||
![]() |
|