[macdonge]

Phil: I found a few references worth considering in regards to the selection of head gaskets.
1. The Ford “Repair Manual, Ford & Mercury V8 Engines” (for ‘37 - ‘48 engines) shows photos on (p. 36) of an old and new design gasket. The old design shows the 3 large trapezoidal centre coolant passages. The new design has the same trapezoidal upper passage, a large round middle hole and a small round lower hole.
2. Joe Abbin’s book “Ford & Mercury Flathead V-8 Identification & Rebuilders Guide” indicates (on p. 7-12) that “The gasket coolant passage designs evolved even if the block and head designs did not, since it was easier and cheaper to change the gasket and just as effective in some cases. Therefore it is advisable to use the latest available gasket designs for each generation rather than NOS where there is a difference.”
3. If you want the closest ‘match’ to your blocks passages, Edelbrock’s 7394 (e.g. Speedway part # 3257394) or Mac’s Part # 91A-6501-C/S/M may do the trick.
4. In my opinion however (particularly in light of references 1 & 2 above), the cylinder heads’ coolant passage configuration is probably the primary consideration in choosing a gasket set. For example, I’ve chosen BestGasket 511C’s to suit the round passages on my Offy heads.

Hope this helps.

Glen M.