first step is to measure the both the block & cylinder head deck surfaces for warp / variation
the 1013 gasket is a steel shim type gasket, it has a wire sealing ring around the chamber where the 8347 is composition construction and does not have the wire sealing ring
composite gaskets are able to tolerate more warp / variation than steel shim gaskets, not sure what the MLS will do if the surfaces are less than perfect but they do require a specific machining finish quality
http://www.crankshaftcoalition.com/wiki/Head_gasket
getting back to my first comment, if the engine won't hold a composite gasket look for the reason why because the composite gasket is the most forgiving, the hardest to knock out unless the problem is detonation or just plain too much darn compression
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