360 Heads
Those are what I call the late model smog head. Same heads I use on my junk. It's actually a better casting to start with if you want to port them. You just have to be careful as they are old and they can get thin in places (BTDT).
I forget the casting number but off my memory, which has been JUNK today I'm thinking its the 586 casting head.
Hope this helps
YR