[djalbin]

Is there any real advantage to the 5.7 ones with the heat flange vs the 6.4/6.1 ones? My plan was to use the 6.4/6.1 gaskets since the header is coated.

The 5.7L factory exhaust manifolds are cast-iron and produce more heat than the ceramic coated headers. So the 5.7L factory gasket has the heat shield.
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[PolynesianPowerhouse]

The 5.7L factory exhaust manifolds are cast-iron and produce more heat than the ceramic coated headers. So the 5.7L factory gasket has the heat shield.
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I figured with the cast iron. Cool. So ill run the other gaskets.