[rotorwrench]

That 1BA casting mark in Merc Cruzer's post indicates that it's a block that originally had the rotator valves and the crankshaft that a Ford-O-Matic or Merc-O-Matic torque converter could bolt up to that came along starting in 1951. These markings would have been there through the end of production in 1953 in the US.

There are a lot of characteristics to ID a Ford 8BA family block even if there is no date code. Most have date codes but not all. After a person finds out all these tidbits, it is easier to nail a manufacturing time frame within 2-years or so. Most date codes are around the right side rear of the intake deck surface. Crankshafts can be identified by measuring the width of the counterweight cheeks. Mercury 255 cranks have a 6.5-inch or so dimension across the cheeks. Ford 239 cranks are smaller.