That is a SOHC 16 valve Honda head. There are 4 valves per cylinder. You probably only "See" 3 valves in the chamber because one of them is an auxillary valve that is hidden behind the casting but there should be some small holes that you'll see or a combustion cup with one larger hole.
EDIT: AREA casting book = PEO 6 is an 84-87 Honda Civic 1.5 SOHC 12 valve with auxillary valve.