If your chain is rubbing the cage on the FD with a 8 speed rear. That does suggest something is wrong. But unlikely the chain. Just glancing back quickly through all the threads, I have to wonder if you have a bicycle that has a mishmash of different components on it. And is no longer anything like it came out of the door of the shop when new.

A incorrect chain line can be one reason. And the wrong FD for the current configuration of the bicycle another. As might just be a simple adjustment of the FD.