But wait, there's more. This is what's left of the No. 8 piston's ring land. Yes, that large chunk of loose material (and others) was riding up and down along with the piston. Amazingly, the bore wasn't shredded despite the fact that the damaged piston land was polished smooth from all the loose bits moving around. This is the result of major detonation and is the root cause of the severe oily blow-by that coated the entire underside of the Comet.