I'm not 100% on this, Ray... I THINK Dennis Carpenter, for one, is offering the older metal style head gaskets.
Victor, Fel-Pro, McCord, BEST, and others have gone to the composite head gaskets. They'll give you a seal that you can't count-on into the future with the old 'tin' ones.
The down-side is that the final thickness of the torqued composite gaskets reduces the engine's static compression ratio by increasing the effective combustion chamber volume.
Here's some specific head gasket information from an article on Ted Eaton's web site:
Here are some known head gasket values for the Ford Y-Block engine.
Best Gasket for regular bores 12.91” X 0.046” = 10.00cc
Best Gasket #572B (3.937” bore) 12.99” X 0.046” = 10.12cc
Best Gasket (4.030” bore) 13.35” X 0.046” = 10.69cc
Fel Pro #7999PT (Permatorq Blue) 12.95” X 0.044” = 9.62cc
Fel Pro Multi-Layer (old design) 12.60” X 0.039” = 8.07cc
Fitz 3 layer (metal,comp,metal) 12.80” X 0.048” = 10.25cc
Fitz 2 layer (metal,composition) 12.80” X 0.050” = 10.67cc
Fitzgerald #0645 (metal/metal) 12.76” X 0.031” = 6.58cc (40+ yrs old)
Flatout #FOG9123.5 (3.830” bore) 12.64” X 0.040” = 8.33cc (copper)
Ford steel shim C1AE-6051-B 12.68” X 0.025” = 5.24cc
Ford steel shim C3TE-6051-E 12.68” X 0.026” = 5.45cc
McCord p/n Mc6392M 12.79” X 0.048” = 10.24cc
ROL Gaskets #HG32120 12.79” X 0.045” = 9.61cc
SCE copper 12.99” X 0.042” = 9.24cc
Victor #1176TC composition 12.95” X 0.043” = 9.40cc
Victor #1176BS steel shim 12.68” X 0.025” = 5.24cc
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The above cc numbers represent the effective volume of the area within the gasket-ed circumference distance and height of the compressed gasket! Notice the striking difference between the steel shim gaskets and the various composite offerings! This is added to your actual cylinder head combustion chamber volume! OUCH!
NoShortcuts
a.k.a. Charlie Brown
near Syracuse, New York