I will try to explain this the best I can. B16 head 2001 ITR cams. I took the head apart and found wear on the distributor side, exhaust cam where the cam lays in the head. Looks like something was on the cam grinding the head as it spins. Its on the actual head where the cam lays and is held in place with the cam cap or cam bearing cap? Dont know what its called. I need to know what the clearence is from the cam to the cam cap/ bearing cap. Sorry if this is hard to understand. let me know and Ill try to answer your questions.

 

Sounds like either oil starvation or improper install. If you can't feel the scratches with your fingernail, it's o.k. If the scratches are deep enough to catch your fingernail-the head is basically junk.