Motor mounts-dumb question but...
#16
I think I'm going to put more thought into this. I'll try to find a bushing with a little more meat to it. I could use a set of transmission mounts myself. The OEM motor mount only uses a single 12mm bolt, but it also has the little alignment pin which does take some shear force off the bolt. If no one cared to drill their cross member, I could use a larger bolt or multiple bolts, but you wouldn't be able to return to stock as easily. Thinking about it, when you floor the engine, it wants to twist, which actually puts force nearly in the direction of the bolt with the way Porsche has angled the mounts. I'd rather run a set on my car for a while before I felt safe offering them to other people without a disclaimer haha.
#17
Three Wheelin'
Thread Starter
Man, go for it. Theres never enough guys like you, Jerry Feather, etc. who can just do this stuff easily. I'd buy the first pair. Put me down for a pair lol.
#19
Rennlist Member
Whats WRONG with the original mounts?
The reasonable alternative =is= the Volvo mount.
I have not in this thread, seen the problem being solved yet.
#20
Chronic Tool Dropper
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Looks to be a bit taller than the stock assembly with the U-shaped upper bracket.
Porsche put a lot of thought into the hydraulically-dampened original mounts. I'm pretty sure that a captive bushing as you illustrate would have none of the motion dampening. It also looks like your design would allow a small vertical and a small lateral movement, but no axial (in line with the bolt) at all, save whatever the compressibility of that little end washer area might be. Right now the hydraulic Volvo pieces are a reasonable replacement option.
Porsche put a lot of thought into the hydraulically-dampened original mounts. I'm pretty sure that a captive bushing as you illustrate would have none of the motion dampening. It also looks like your design would allow a small vertical and a small lateral movement, but no axial (in line with the bolt) at all, save whatever the compressibility of that little end washer area might be. Right now the hydraulic Volvo pieces are a reasonable replacement option.
#21
I measured 3.5" from the bottom to the top of a fresh, solid rubber mount. The mount I drafted is the same height from the bottom plate to the top plate.
The only dampening would come from the rubber squishing between the tube holding it on one half of the mount and the bolt pinning it to the other side of the mount. It wouldn't be much, but that is usually what people use polyurethane bushings for I believe. I'm looking for a beefier bushing that would dampen a little more though.
You know how some of us are, we like to create a problem to solve. It leaves more OEM stock for you.
Looks to be a bit taller than the stock assembly with the U-shaped upper bracket.
Porsche put a lot of thought into the hydraulically-dampened original mounts. I'm pretty sure that a captive bushing as you illustrate would have none of the motion dampening. It also looks like your design would allow a small vertical and a small lateral movement, but no axial (in line with the bolt) at all, save whatever the compressibility of that little end washer area might be. Right now the hydraulic Volvo pieces are a reasonable replacement option.
Porsche put a lot of thought into the hydraulically-dampened original mounts. I'm pretty sure that a captive bushing as you illustrate would have none of the motion dampening. It also looks like your design would allow a small vertical and a small lateral movement, but no axial (in line with the bolt) at all, save whatever the compressibility of that little end washer area might be. Right now the hydraulic Volvo pieces are a reasonable replacement option.
You know how some of us are, we like to create a problem to solve. It leaves more OEM stock for you.
#22
Three Wheelin'
Thread Starter
Speedtoys, it's not about the Volvo motor mounts, those have proven themselves. However it could be a good compromise between the totally rigidity of 928MS's solid aluminum mounts (problematic on street cars) and the soft OEM mounts or Volvo mounts.
#24
Nordschleife Master
This mount you made will make the engine site over 3" too high.
The factory mount has a stamped piece which is shaped like an upside down U which the majority of the mount is concealed in.
I think it would be best for you to climb under the car and look at it first.
#25
If you need a guinea-pig for the poly's when you get one(or some) made up, I'm ore than willing to pay for them and test a pair, I have to change my steering rack (again) anyways...
PM me.
And much thanks for putting in the work for this!
#26
Three Wheelin'
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#27
Nordschleife Master
https://rennlist.com/forums/928-foru...ding-jigs.html
He was also working on transmission mounts too IIRC.
#28
Chronic Tool Dropper
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Early car owners have the option to drill their early crossmembers for the later mounts, or buy a used later-styl one and swap it in with the newer-style mounts.
#29
Are People really interested in this ? How much do they get for new rubber mounts ?
Does anyone have any old mounts to strip for hardware?
I could make these if there was interest. Same size,shape just hard urethane.
Does anyone have any old mounts to strip for hardware?
I could make these if there was interest. Same size,shape just hard urethane.
#30
I have no doubt that you did this, but that doesn't mean this will work.
This mount you made will make the engine site over 3" too high.
The factory mount has a stamped piece which is shaped like an upside down U which the majority of the mount is concealed in.
I think it would be best for you to climb under the car and look at it first.
This mount you made will make the engine site over 3" too high.
The factory mount has a stamped piece which is shaped like an upside down U which the majority of the mount is concealed in.
I think it would be best for you to climb under the car and look at it first.