Oldsmobile engine casting number identification

[the baron]

Hi Guys ,

Sorry to annoy you again with my numbers , but I found the casting number on the Olds engine I have into my Burb

I did a search on the net , and as the casting numbers for the Chevrolet engines are easily available in books , for the Olds ones , it seems almost impossible to get ( or I'm too stupid to find the right site )

the casting numer is 554965 2A ( that 2A being bigger in size )

this all because I'm convinced that my engine is 350ci , but it could be also a 307 or a lesser cubing engine ( 260 ? )

BTW , I have EGR on it , so I presume a 307 is out of the question...

I was unable to read the serie number on the engine , too muddy/greasy & I'm not a contortionist either ...

Thanks y'all

the Baron