I just measured my old passenger mount and got 92mm which is consistent with what revshift just posted as a new mount...
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Ok ... now you have me curious ... so how many miles/years on your old passenger mount? That's the one that takes the most abuse. Interesting that you have "as new" measurement height.
Filippo
I'm not sure if it had ever been replaced, I bought the car at 82k and it now has 102k. I have all the service records so I could go through and see if it was done before I purchased the car but I don't recall seeing that before. Car is a 2008 e92. The mount i measured is also the mount I posted a picture of before with the tear. I tried my best to replicate the way you showed how you measured.
Top mount is angled. I measured from the back of the stud. When John and I exchanged measurements privately via email, he measured like I did so we could compare directly. Normally he measures from the front (which has a lesser length), and that is what he posted here. Hope what I said makes sense...
Filippo
Filippo
Ok that makes sense, I reread a previous post and saw that he gave you a measurement of 99.x mm to the back of the stud for new oem. I took my measurements to the back of the stud as well so I was incorrect in saying I had the same measurements as new oem.
The unloaded height difference is not the point, it is the loaded height. If the new poly mounts don't compress at all and a new stock one does that's all it would take. An old worn out stock mount that compresses even more might measure the same unloaded as new and still show a much greater height difference loaded vs poly.
We take the loaded height into account when designing mounts. Surprisingly, a brand new oem mount does not compress very much when the engine is placed on it. We are talking maybe 1/16" compression. Our 80A mounts do compress a tiny bit under load as well. The oem mounts compress more and more over a long period of time. Our mounts maintain the original intended ride height of the oem mount. Keep in mind, we have been making polyurethane motor mounts for 12 years now. Everything being discussed here was accounted for when designing these mounts. We took our time designing them and they ended up being the most involved and thought out mounts that we have come up with so far. Our mounts do not raise the engine or lower the engine when comparing to brand new oem mounts. Maintaining proper drivetrain geometry is very important to us.
I want to add that we designed our mounts to maintain the maximum height of installed new oem mounts at the request of several N54 owners, especially, single turbo guys. Some top mount single turbo guys told us that the turbo ends up having clearance issues when the oem motor mounts get worn and compressed. We actually had requests to make motor mount spacers to raise the engine which we did not do. We could have dropped the engine 1/4" to lower the center of gravity but that would have created issues with the guys that have tight tolerances on the exhaust side. So we chose to keep the engine at the top of the factory location. We have installed the mounts on a few cars here and a few local guys have installed our mounts themselves. None of these cars have any clearance issues or drivetrain alignment issues what so ever. We have been told that these mounts are perfect from multiple customers now.
The differences that we are discussing here are around 0.030" which is the thickness of a credit card. That is the compression difference with the weight of the motor between our mounts and new oem mounts. You have to keep in mind that our 80A mounts keep the engine in place wayyy better than the oem mounts. Your engine rocks back and forth and moves up and down while driving on oem mounts. The engine barely moves at all with our mounts. So the drivetrain geometry is maintained much, much better with our mounts while you are driving. And that is the whole point in upgrading to performance engine mounts.
The differences that we are discussing here are around 0.030" which is the thickness of a credit card. That is the compression difference with the weight of the motor between our mounts and new oem mounts. You have to keep in mind that our 80A mounts keep the engine in place wayyy better than the oem mounts. Your engine rocks back and forth and moves up and down while driving on oem mounts. The engine barely moves at all with our mounts. So the drivetrain geometry is maintained much, much better with our mounts while you are driving. And that is the whole point in upgrading to performance engine mounts.
No but you are talking about a difference of 0.010” to 0.015” when installed. Basically, there is no real world difference in mounting height between the two hardnesses.
Ok a couple hundred miles of use, here are my first impressions. A couple caveats. My suspension is all ball joint/spherical bearing. Also I'm running Rogue Engineering rubber trans mounts and AKG cups. My car also has extensive sound deadening. No idea how these factors play in. I will say, before I installed these motor mounts, my configuration is pretty low NVH - slightly more than stock at worse.
That said, I have the 80a mounts. First 100 miles of driving, I would be hard pressed to notice much of any difference in NVH. The last 100 miles, I've had vibration at idle and on deceleration. Pretty obvious vibration. I've not been able to track it down - checked the exhaust at the downpipes this morning. I also checked the torque on the motor mounts. No issues. I'm not attributing this to the motor mounts directly at this point - I suspect something is loose.
Filippo
That said, I have the 80a mounts. First 100 miles of driving, I would be hard pressed to notice much of any difference in NVH. The last 100 miles, I've had vibration at idle and on deceleration. Pretty obvious vibration. I've not been able to track it down - checked the exhaust at the downpipes this morning. I also checked the torque on the motor mounts. No issues. I'm not attributing this to the motor mounts directly at this point - I suspect something is loose.
Filippo
I had a black forest industry PU amount starting melt and deform from the downpipe heat in just two weeks of winter driving. The driver side held up just fine over the years since it doesn’t really get that hot over there.
I would check the passenger side mount to make sure you don’t have the same problem.
I drove for 8 hours almost all in stop and go traffic and mine is fine so far fwiw. I am using the heatshield they provided, it can't hurt imo. This is after I went single turbo.
I am really curious if you replace the poly in your mounts if they will be great for 100 miles again. Maybe it is just that they aren't very elastic so once they deform they stay that way. It makes me wonder if the best method is to go with the stiffer inserts and just mount on a rubber pad. If my 034s have failed I'll either be doing that unless is mounts drop back down to sane pricing.
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