Anchor Motor Mounts $18 each
#211
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Dave,
Brilliant point - I will try and see if they will fit the later cars.
Roger
Brilliant point - I will try and see if they will fit the later cars.
Roger
__________________
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
Does it have the "Do It Yourself" manual transmission, or the superior "Fully Equipped by Porsche" Automatic Transmission? George Layton March 2014
928 Owners are ".....a secret sect of quietly assured Porsche pragmatists who in near anonymity appreciate the prodigious, easy going prowess of the 928."
#213
Nordschleife Master
Engine shocks reduce movement, solid MM have less movement than hydrolic. What gives the glassy feel is allowing some movement, adding shocks would just further reduce the movement of the engine relative to the chassis transmitting more vibration.
#214
Rennlist Member
Engine shocks provide some resistance to initial movement, true, but more importantly they damp resonant frequencies -- they were originally fitted to cars with solid motor mounts for this purpose. Resisting movement is a beneficial side effect; the primary purpose as with the hydraulic feature of the later mounts is to act as a damper.
#215
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Originally Posted by SharkSkin
I know the later cars continued to have the mounting boss for these shocks for many years after they stopped using them -- did they stop tapping the threads in them at some point or no?
Can't remember off hand if later style rear subframes have mounting points for '78 MY gearbox shocks. These were deleted when battery box was changed to be part of the body and one of two gearbox mounts got bigger. They might be useful in later cars also. Not sure about PSD boxes but I think at least all earlier transmissions have mounting points for shock mounts in casing. Also without threads.
Anyone know what parts transmission shocks need to mount into rear subframe. PET only shows locking nut but I suspect something else is also needs. Maybe couple of washers and some rubber in between.
#217
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H,
Don't spoil the fun - I was looking forward to putting Koni adjustable shocks on my engine.
Now should I go for external or internal adjustment???
Now that is a really good question.
Don't spoil the fun - I was looking forward to putting Koni adjustable shocks on my engine.
Now should I go for external or internal adjustment???
Now that is a really good question.
#219
Rennlist Member
H, the later solid mounts may isolate better than the early ones. I could tell the difference between having one engine shock vs having two on my car.
#221
Nordschleife Master
Could be the old engines didn't run as smooth and needed the shocks etc.
My guess is that the extra shocks were a type of "insurance" that Porsche found unnecessary.
In modern cars I think an engine shock is most often used to manage torque, not vibration, thats the way they are mounted for most FWD cars.
My guess is that the extra shocks were a type of "insurance" that Porsche found unnecessary.
In modern cars I think an engine shock is most often used to manage torque, not vibration, thats the way they are mounted for most FWD cars.
#222
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Solid rubber ***** bounce , ballons full of liquid do not...the later liquid filled mounts are designed to BOTH support the engine and absorb vibration. Clearly solid rubber mounts are vastly superior to collapsed liquid mounts. Solid rubber mounts use the engine shocks to absorb vibration and more than one rennlister with the old style has commented that the car feels better with new engine shocks. The aftermarket solid rubber mounts are probably "good enough" after all millions of Ford owners use them after all , I have never heard of any of them fitting Porsche liquid mounts !
#223
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Originally Posted by danglerb
Could be the old engines didn't run as smooth and needed the shocks etc.
My guess is that the extra shocks were a type of "insurance" that Porsche found unnecessary.
In modern cars I think an engine shock is most often used to manage torque, not vibration, thats the way they are mounted for most FWD cars.
My guess is that the extra shocks were a type of "insurance" that Porsche found unnecessary.
In modern cars I think an engine shock is most often used to manage torque, not vibration, thats the way they are mounted for most FWD cars.
Similarly, with a FWD car having a shock on the engine mount, the shock will not have any effect on how far the engine moves with sustained torque applied; it will only slow the movement to that position. The deflection of a FWD engine like you describe will be exactly the same with or without the shock, once the torque has been applied for a second or so.
Shocks resist transient movement, they have no effect on the ultimate deflection when the force is applied for sufficient duration.
#225
Nordschleife Master
Originally Posted by Jim bailey - 928 International
Solid rubber ***** bounce , ballons full of liquid do not...
What sort of forces do the mounts have to deal with on a 928?
Is it it just engine vibration, or is it also torque related?
**** edit, I typed hydrolic shocks, but meant hydrolic MM above.
Last edited by danglerb; 01-11-2007 at 03:45 PM.