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Small block engine issue HELP (408 stroker) headgasket? Broken rings ? Intake gasket? Or???

Thank you Doug I appreciate you taking the time to respond with that amount of detail. I'm headed home from my work trip tommorow and hope to get after it this weekend and report back. If not this weekend I will report back once I find the issue. Thanks all have a great weekend .
 
Just want to thank you all again for your helpful responses after a crazy few weeks of travel for work I finally found some time during the Thanksgiving holiday to get the motor disassembled after removing the intake I was immediately met with a small piece of metal fragment from a gasket I initially assumed that the gasket had been removed from the previous intake install and accidentally dropped into the top of the motor. After moving the passenger side cylinder head it was evident immediately what the issue was the fire rings on the head gasket for two of the cylinders were completely exploded and that metal piece I had found beneath the intake was shrapnel from one of the fire rings exploding. After doing some research it appears the proper head gasket was not used for the cylinder heads that have been put on to the motor ( aluminum speedmaster pce 281.2149). Speedmaster recommends a steel MLS type gasket and what had been used was a felpro 8553 PT. I have since removed the passenger side cylinder head and found that two of the cylinders on that side also exhibited signs that they were going to blow pooching up of the fire rings and cracks in the gasket were very evident I have since ordered an MLS headgasket set and plan to get the motor back together here in a couple weeks . Again I would just like to thank everyone for the help and be thorough here in my response so that anyone that comes across a similar issue in the future can be hopeful that their motor may not be completely destroyed below are some pictures of the head gasket issue.

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I've seen the gasket blow in that area on my blown 340. I agree the gaskets may be inferior. A couple of notes. Make sure the deck surfaces (head & block) are flat and did not suffer any erosion. Also double check TDC on #1 piston vs the timing mark at the balancer. In my case the issue was detonation from excessive timing.
Doug
 
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