valve chatter 360 magnum

I don’t think he has a lifter problem,,,,,I think he has an internal problem,,,,or a bad gauge .
But,,,I don’t think it’s the gauge .

Evidence being of clatter at idle rpm,,,,,classic textbook example of low pressure .
And,,,,,low pressure around 2500 rpm,,,,another example of improper clearance somewhere inside .

When we fired my son’s new engine,,,,it was 75 at cold idle .
It was 45 at warm idle,,,,,,after the throttle was applied,,,,it was right back up there .
Runs at around 55 hot and at speed ,,,,,,really good engine so far .

I’m not trying to argue,,,,,just saying,,,,something is not right,,,,,roller lifters or not .

Tommy