340 Block Bored to 4.160????? Help

So again, in what way were the rings 'cooked'?

With this bore size and the right pistons, and this cam, then the DCR may be so high as to lead easily to detonation. Got any pix of the piston tops? Any little speckled pits on the piston tops? Any idea on your ignition advance settings? Did you ever hear any pinging? (And how good is your high frequency hearing?)

Just thinking of what else can cause overheating and 'cook' rings.

This size in KB's? Yeah, that does not make sense for Chrysler slugs.... a few GM and Ford ones show up that have something near to the right compression height and diameter. And we have no idea how much the deck has been milled on this block.