[Excaliber]

Why .070? Bore it another .003 or like Ron said, .065. Then order new pistons. 427's (I know it's a 428) typically bore at .003 segments. Mine, with final hone is actually .019 overbore (was .017). My new pistons have .0035 clearance. Of course these are CUSTOM ORDER pistons and cost a bunch!

By the way, YES, my new pistons are ready to ship from Gessfords!