Worked fine on the old 451 with B1-B/S heads. This is from a post I made about gaskets for the stealth heads: If you get the Fel-Pro KS2110 gasket kit ($55 for a full gasket set from Summit Racing - minus valley tray) the 8519PT1 head gasket will fit the stealth heads. The 8519PT1 measures 4.5" bore diameter and is 0.040" thick, or about 10.4cc (calculated.)
