99 1LE SS

iTrader: (1)

I rebuilt my motor last year and added an LS6 cam and took .015 off the heads now i have valvetrain noise. On autotap it shows knock retard which drops to almost zero at high rpms. I double checked all of the rockers to make sure none had came loose. I checked my pushrod length and i have .025 preload on the lifters which is about half of stock. Is this enough preload or is more needed.
Ive driven the car almost 3000 miles including some track trips so i know its not bottom end noise cause i would have lunched something by now. The car runs great pulling a 12.1@112 with the ls6 cam stock unported heads and the stock pcm.
any and all help is greatly appreciated