lost a piece of piston...Stumped?

Shoot, I've lost a complete piston, Rod, cylinder wall & a valve in one whack. They disappeared into thin air. I found pieces of parts in the carb! After I put the new motor in and fired it off, there were pieces and schrapnel flying out the exhaust... A lot of it was caught in the mufflers.
Louis,
Was that the motor from the 70?