Ok, there's been so many unique problems with lifters tapping that i'll start a fresh thread...I've just built a fresh 355, roller motor, and i'm positive that I have all my valves adjusted properly.

What happens is that I can get the car started up, and it runs perfectly! If I let it sit overnight, then crank it, the lifters tap like crazy for about a half a second, maybe a full second...after that, it's excellent.

I've tried going over all the valves again, the messy way with the valve covers off...loosen the rocker till it starts tapping, slowly tighten it back till it stops tapping; when it stops tapping, tighten slowly another 1/2 turn.

I've pulled out the lifters, inspected them, took them apart, and saw nothing wrong? any suggestions?

 

Try a quarter turn in. Personally i adjust a hydraulic by the speed of the pushrods spinning. If you have them too loose they spin like crazy pretty much constantly. Too tight and they barely turn at all.
What brand of lifter? I know someone with Comps that is changing them out because he finds them to be too noisy.

 

they're just some generic stock roller lifters from the machine shop that done the machine work