1967 915 heads any good?

i HAVE A SET OF 915 BIGBLOCK HEADS ON MY 383 AND I WAS TOLD THEY WERE CLOSED CHAMBER AND ARE GOOD TO RAISE COMPRESSION ARE THEY A GOOD HEAD FOR MY MOTOR ? OR DO I SPEND THE MONEY ON ALUMINUM HEADS OR ? i HAVE A PURPLE SHAFT CAM BUT I DONT NO OF THE DURATION AND A 1968 HP BLOCK .