I have a 347 stroker disassembled in my garage. The engine was "professionally" rebuilt a few years ago.
After running about 1k miles, the engine gave up. The car was brought to a mechanic that wasn't able do diagnose the problem and another engine was put in the car.
I have the engine now and I have been taking it apart. What I have found is that 4 of the pistons have been damaged. I'm pretty sure the cause is detonation/knock.

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Compression Ratio - Calculation and recomandation