ID Chevy engines
I don't see that block c/n, but there are two similar:
• 14015445: 1975-'90; 454; car and truck
• 14015543: 1987-'90; 454; 4-bolt; Gen-5
The heads are rectangle port w/325 cc intake port volume, decent heads when matched up to the rest of the engine. They were a replacement/crate engine head.