180ways2slide

i have about 8k on my motor since rebuild sr redtop cp pistons eagle rods .020 over microtech ltx8s, here is my problem i hear like a tapp/knocking noise at idle it is not there all the time, sometimes louder than normal and other times gone completely. also if my a/f ratio richens up it comes louder only at idle. i dont here it through my rpms and my performance has not changed.

i heard piston slap only happens at cold start and a spun bearing gets louder through rpms, it sounds likke its bottom end but the sound plays tricks with your ears cause it an sound up top at times. what do u guys think, a friend said maybe piston wrist pin or something like it what do u guys think. i kno its hard not being able to listen to it but is there something to look/listen for if it is bearings???