Standard race car practice is to make the engine/transmission a rigid part of the chassis. If there was such a problem as you state, then I would have to believe that the various sanctioning bodies would have outlawed the practice many years ago for saftey concerns.
And I believe you are making a big "todo" about nothing. As I have stated; I have run steel motor mounts in cars past, I did not experience the problems that you have raisen. Nor did my cars rattle apart and I still have all my teeth firmly afixed in my jaws.

Would I run them again, maybe, if the need was warranted.

Really, all the engine with the new style mounts that I have observed, have more then 3* of movement. But then they are all over 30 years old now.

You know what kevin, just do it.

The thing will run without it, the mount wont break off, no binding/smacking when you launch full bore from a stoplight because you resent being passed. But that's it; that's the limit of the 'benefits' you'll receive from re-designing the Chrysler engine compartment, because that's what you're doing; you've told generations of superbly qualified engineers to stick it in their ear, you know a better way to do it. Of course, all the experts in the HOT ROD/Musclecar books say solid mounts are a wizard idea, along with super coils and yellow wires itty-bitty fan pulleys and all the other bitchin' tricks that made them rich and famous as builders of fine automobiles. What? Oh.


You are right though; those cracks arent magically going to appear overnight because you launched hard once, or twice, or three times. So feel free to do it your way and in a few years when you quietly discover said cracks and take your car to a welding shop to have it fixed, we'll all turn our heads and pretend not to see a thing. It's just easier that way

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I've been calling it as i see it for my entire life and that's not about to change. Take it or leave it.