You may have a 235 cu in motor from 1954? with full pressure oiling if there is a '5' missing from your number that you gave us.
Check out this page from the Keith Hardy site and look at the info on 1954-57 engine serial numbers.
http://chevy.tocmp.com/models/engine.htm Do you see the change in the engine code ID system from 53' to 54' and after. 53' and before has letters then numbers. 54' and after has numbers then the letters for the engine manufacturing site etc.
So looking at the 1954 engine codes, your number may be the
0849347 = unit number
F = Flint man. site
(5)4 = Year (should be '54' if my theory is right)
Z = Regular 235
Finding a casting number on your engine block would be very helpful. Check this site for a good list of 235 block casting numbers.
http://antiquechevytrucks.com/Content/Engine%20Information/engine_235_body.htm Finally from this Stovebolt site there is a tech/info article on swapping the 216 for a 235 which may help you ID your engine.
http://www.stovebolt.com/techtips/engine_swap_216.htm So, possibly recheck your engine serial number and find that block casting number.
Let us know what you find. Hope the above was helpful.
