Cylinder head cracks?

[Ratau]

I saw the topics about the small cracks between the valve seats. I found a hairline crack on # 4 between the precup and the inlet valve. Is this critical and how thick is the casting in this area?

[Robyn]

I would have the head magged and pressure tested.
These heads have a habit of surface cracks but unless you pressure test them you cant be sure. Might also be a good idea to have hardened seat put in that area unless the crack is too deep.