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After driving for an hour, I got home, shut the car off. Went inside for about 5 minutes, then came out and started the car. I heard a racket like marbles thrown down a hallway, after running for 2 seconds, I restarted. Same thing, ran a second died. Then I thought that wasnt good. I pushed it into the garage and pulled off intake manifold. It had all kinds of small aluminimb parts in it. I then pulled off passengers side head off to discover the parts of piston in a clump. Dont see any valve strike marks, but inside head looks like acne. Only a couple scratches in cylinder from piston rod pin. Dont know why piston blew up. All stock except DOD delete with stock LS3 cam and lifters and springs. Did that about 3 months ago. Hell, I think I could just put new piston in after I deglaze cylinder, and put it all back together. What do you guys think?
 

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I've seen low speed failure just like this with bone stock LS3s and LSAs. Crazy.

BTW, this typically happens when a bearing starts to turn, and it finally gives.
 

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Valve Seat came out

I now know why the piston came apart. It was the intake valve seat that came unset. It worked its way loose, then stuck valve open, then got cracked and them smashed up piston. What a mess. Anybody know of a good place that does valve seat replacements?
 

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damn man... that sucks. Good luck on the rebuild!
 
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