Stopping the knock: Lower compression and ported heads...

It does result in piston damage.......but it takes some TIME to do it.........OR rather quickly under severe load. I've given all of my theories about your detonation, only to be rejected and mocked via PM so I'm not contributing to that anymore. It was detonation. That's my opinion. It's also my opinion it was not caused by too much compression. But you could put that together through all of my posts.......hopefully.