A crazy guy responded to my thread on the other board and his hypothesis sounds almost exactly what im experiencing.
"If it's a clacking noise that cuts in for half a dozen taps and then quits, then repeats, then disappears until the next cold start.....then that is more than likely the start of a lifter problem. It's sporadic because at this stage it's all about a problem lifter retaining or not retaining a cushion of oil internally.
If it's holding it's oil then there will be no noise, as it loses oil inside then there's no cushion and you're getting metal to metal tapping....until such time as it can hold it's cushion again.
==Broken stuff like valve springs and rocker arms wont normally give off anything but a constant noise in time with engine rpm. The noise won't cut in and out.
If your lifter keeps hammering and metal surfaces get damaged ie lifter roller & cam lobe, then the sporadic (hydraulic natured) noise you are hearing now will blend into a constant (mechanical damage natured) noise....in time with engine rpm with no respite."
Time for a cam swap seems to be in order, since I highly doubt warranty will cover my lifters with headers and new UDP.
