Lifter noise?

Check oil psi.

But the first thing I think of is whether or not you have the correct preload on the lifters another words are your pushrods too short.
Oil PSI is fine (first thing I check). You could be right about the preload though as I believe my pushrods are about 1/16" too short. I have 273 rockers and most of the adjusters are maxed out all the way down.