Technical 1939 vs ‘41 flathead heads

i have 1939 (9T) flathead heads (top picture) and 1941 (A) heads. The ‘41 heads looks like they would have much higher compression with their smaller combustion chamber. Does anyone know what the compression is on a stock 1941?
Are there better head with higher compression?

 

Have them shaved about .125". Just check for piston kissing the head( the engine head, that is)

 

The "9T" is a truck head. They normally had lower compression than the p***enger heads.