Strange hole in S14 SR20 head and cam question

[240sx1234]

Updated: Found the answer regarding the hole and the cam but now I have a question regarding damage to the pistons. Let me know what you think



I bought an SR20 from a friend and am in the middle of tearing it down to make sure everything is good to go before I put it in my car. When I was taking the cams out I noticed this:





This is on the rear of the head on the exhaust side, right behind the last spot where the cam is (technical term?) Is that hole normal? It seems like it could be functional but I have no experience with SR20's and it didn't look like a perfect circle like I would assume the manufacturer would make.

Another question, is the cam supposed to be so close to the head here? In the picture the cam has already been loosened and isnt seated. It just seemed rather close, but again I have no idea. Just trying to get some response. Thanks!