I assume this is not a built block? If you can debur the coolant gallery out while you have it down you would benefit from doing so. Manufactures usually match up their pistons and rings. I know you can get +01 rings for the Weisco pistons not sure about the OEM> Don't use 1 (88mm) size larger rings their not made for what you purpose, but if the cylinders are still stock you could use the +01 stock oversize. I suspect you'll be running above stock boost which means a larger gap anyway..
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