I have a 455 that the owner before me installed not sure what year it is or where the stamp or casting numbers are?
It does have large spark plugs and a EGR on the intake, so I was kinda thinking about 1969.
Also what are the good heads for this era of engine?
Steve

 

If the intake is original to the engine, it's a 73-76 motor. EGR was not used prior to 1973. Check the large raised letter next to the No. 1 and No. 8 spark plugs. I'll bet it's a "J", which would signify the smogger heads used on the 73-76 motors.

To definitely learn the year of the block, you'll need to check the VIN derivative. See this thread:

https://classicoldsmobile.com/forums...html#post13537