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Join Date: Aug 2004
Location: Nanimo, B.C. Canada
Re: Bow Tie block vs standard mark 4 block?
The early BowTie block that you listed has standard MkIV oiling as well as stock lifter bores and height. These blocks came from the factory rough finished for a 4.250" bore. You'll have to check what that one has been bored out to. These blocks do have reinforced decks, lower bores, bulkheads, and main cap areas, unlike standard 454 or 502 engines. The block can be bored to 4.560".