Manufacturing method for cylinder head

A manufacturing method for a cylinder head comprising the steps of:

• preparing a cylinder head material having a cylinder block matching surface with a cylinder block and an inner wall surface of an engine combustion chamber in a same plane, wherein at least three port holes corresponding to at least one intake port and at least one exhaust port are formed on the inner wall surface;
• attaching the cylinder head material to a masking member to mask a non-film formation region of the inner wall surface and the cylinder block matching surface;
• after the attachment of the masking member, injecting film material particles through the masking member onto the inner wall surface of the engine combustion chamber to form a heat shield film;
• and
• detaching the masking member from the cylinder head material after the formation of the heat shield film,
• wherein the masking member comprises:
• a matching surface mask portion that masks the matching surface with the cylinder block;
• port hole mask portions that are connected to the matching surface mask portion directly and mask openings of the at least three port holes;
• and
• a between openings mask portion that masks at least one narrow region which is sandwiched between openings of two adjacent port holes of the at least three port holes and has the shortest distance between opening edges of the two adjacent port holes of the at least three port holes, and is directly connected to both of the port hole mask portions that mask the openings of the adjacent port holes of the at least three port holes, and
• wherein the matching surface mask portion, the port hole mask portions and the between openings mask portion are coplanar.