My neighbor's 327 started running like crap. When we pulled the rocker cover from the left side we noticed the third rocker from the front is barely moving with the engine running and you can even tighten the rocker ALL the way down and it still has some ticking and no significant movement. Bad lifter???

 

Rolled cam lobe

The cam and lifters are now garbage

 

Bummer. I was afraid of that. Thanks RB.

 

Make sure that the pushrod is actually sitting on the lifter. If it was bumped off during installation then all the tightening won't do anything and it wouldn't move while the engine was running. Not very likely but it's possible.