Hey all- I just got an old small Nailhead 264? Cleaned it up yeasterday to find the block numbers to help ID the year and cubic inches. My motor does not have a harmonic balancer but does have the very early fuel pump. I think '54 or '55. The real problem is the 1's or I's (that sometimes represent 1's). So here goes. The block number is II05II34. Any help would be very appreciated.
The engine serial number 11051134 decodes like this (yes the I's are meant to be read as 1's): 1105113 = sequence number unique to engine, range for 1955 is V720080 to 1460022 4 = Series 40 (Special) (Note V prefix for V8 was not used after engine number 999999.) This makes your engine a 264 out of a 1955 Special. The 264 was used only in the 1954-1955 Special and didn't have a harmonic balancer as you've noted.
The Jalopy Journal
