Quote:
Originally Posted by bruce.augenstein@comcast.
Next, let me advise you to think about engine mounts, what they do, and the very basic principles involved. The thing is, you're trying to suppress individual firing impulses, and you can't just stiffen up the mounts by, say, 50% to suppress 50% more energetic pulses, or else the mount stops effectively doing what it's supposed to be doing, and you get that sitting-in-a-blender feeling. So you're going to get more engine/transmission movement in a longitudinally-mounted layout with high torque than with a lower torque application.
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Sure about that? I don't think so. I think engine mount stiffnesses are governed more by the total magnitude of the twisting torque of the engine. Sure that is the result of many individual firings but I bet you could not pick up those really high frequency signals in say the resulting lateral movement of the gear shifter. Lots of magic can be worked with suck things including stiffness, non-linear stiffness, damping and totally different performance for translational DOFs vs rotational DOFs. In short I'd be willing to bet any decent NVH engineer could prevent the vast majority of this "unwanted" shift lever movement while not making you feel in gory detail all of the NVH from the engine.
Anyway, I think we finally, basically, agree - part intent, part lack of attention to NVH.