I probably didnt phrase that the best....as you have seen yourself detonation can produce a variety of side effects...all pending on the root cause.
My position on your conditions is that it is not detonation. Detonation will not crack a block without significant other evidence/conditions occurring.
Number 4 chatter is a given when things are less than optimal....and that is evident in the photo....my questions where what else are you seeing in conjunction with that?
I will post more pictures later of piston tops,combustion chambers. What else would you like to see?
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