[markjohnson]

I'm pretty sure that 1.72 is the exhaust valve for early BBC closed chamber heads. The intakes were usually 2.06 or 2.19. I don't know what came with a 2.11 intake valve. Tell you what though, if those are NOS GM valves, I'd chuck them straight into a trash can. They are the reason that there are so many CE replacement engines out there. When that head snaps off that valve stem, the results are usually catastrophic. Even the cheapest Manley one piece street valves are a vast improvement.