Jax White TA

I have a strange knocking/tapping noise coming from the engine as of the other day. Now, this is louder than a bent pushrod, but quieter than a rod bearing. The car is not pulling any knock retard even free revving to 4K. I have pulled the rockers, and the pushrods (chromoly) are all straight. Could my cam have collapsed a lifter? I used a mechanics stethescope on the motor and it wasnt louder on any one spot of the motor. It's very obvious though standing next to the car while idling. It's not missing and seems to be running normal. Could it be carbon knock? I havent sprayed it in a while but have had several WOT runs Saturday night. Wouldn't that have cleaned out the cylinders of carbon? I'm stumped.

TIA,
Dan <img border="0" title="" alt="[Confused]" src="images/icons/confused.gif" />