Hi all I picked up a 261 engine that has me flustered. The casting number is "3769925" which should be a '58-'62 261 block. The casting date is "A 5 6" which should be Jan. 5, 1956. The serial number suffix is F 255N Which I think means 2nd series 1955 The dowel pin is present for the optional full-flow filter along with the 1/2" ports next to the smaller bypass ports.
So, just what the heck do I have here...? Nothing seems to match up!
