340 is knocking

I had a MP cam and lifter kit that had a bad lifter from the get-go. It wouldn`t pump up and was tapping like an Irish dancer. It was no problem identifying the lifter as loud as it was. It did had me worried at first though. I finally replaced it and the tap went away. If it`s a rod bearing you can pull a spark plug wire off a cylinder one at a time and see if the tap abates some. Pulling the plug wire will usually quiet the cylinder that`s the culprit whether it`s the rod, a wristpin, or something in the valvetrain like a bad lifter. Does it make more noise when the engine`s cold or hot?