Hemi starts to miss and it looses power on top end ?

I have a hemi predator on top end it wants to sound like its floating the valves but I replaced the springs and valves with heat treated oem ones any ideas on wut it could be I changed coil and plug also still does it ?
 
Drop back on that 39 jet to a stock jet 30/31 and see if it goes away. 39 is a lot of jet for what you have explained.
 
.031" to .039" is a 58.3% change in jet area!! Kind of extreme!
Something I've seen, kind of far out, but is the spark plug cap loose on the spark plug? What is that thing call that screws onto the top of the spark plug. Those need to be tight or the problem you're describing could occur. I've seen it myself.
Of course being rich could possibly be the problem, but if it was me, I would make a 1 jet size change and see if things get better.
 
Start with the factory jet and move up from there. I guarantee you won't go far if you are still on the factory air box and factory exhaust
 
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