Help! Small block 360 has a knocking sound

200 psi seems kinda high. how modified is this engine?

the funny thing is I don't know, I didn't build this engine. Whoever built it put a competition cam of some sort in it, and Keith Black 9:1 pistons, that's all I know. Besides, I think the reason for the super high compression is carbon build up, this car was my daily driver for quite a while.