The ID/Code is located on the top of the left center exhaust port on each head.
All used shaft mounted rockers.
ID/ Casting Code Year(s) CID CCs Number Notes 10 1949 10 1956 16 1957 371 18 195? 20 394 23 1964 394 Seen on 394.
Intake, Exhaust Port Sizes
1954 and 1955 324s' have smaller intake ports and valves than the 1956 engines. 1957 and later cylinder heads will physically bolt on to 1949 to 1956 engines, but the port matchup on intake maniflolds will be off because different cylinder deck heights are used. 1957 and later cylinder heads have larger coumbustion chambers and valves.
[ Thanks to [email protected] for this information ]
Combustion Chambers, CC's, Interchange