I had the same problem with my intake gaskets. They tore and leaked oil. I believe it was from over torquing the manifold bolts, and possibly improper sealant.
I think I have it whipped. I used Gaskacinch on the head side, and a thin smear of RTV on the intake side. That way the gasket is firmly glued to the heads, and the Intake side can slide and expand as you tighten up the bolts and it goes through heat cycles. I also don't get carried away with bolt torque.
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