It doesn’t matter one bit if they’re 15, 17, or 21 lb/ft. If they’re tight and making noise you have another problem. Likely preload on the lifters is wrong.
Since he said he may have them too tight or too lose, I was assuming he didn't have them tightened completely. He may not have known they do tighten down all the way. That would certainly make for a noisy valve train. lol
