What about 150 lbs seat with 350 open? I have the same valve springs as his and that's what I measured mine at. To me that seems pretty darn high to break in a new cam. JMHO
It's amazing what another 10-15psi will do to a cam, though it;s not a major step it's just enough to possibly destroy something.
150 is 10lbs more than I would go max seat for break in, it's possible it will work, and in some cases has , but to me it's rolling the dice.
I like 120 seat for break in.
you could run 350 open but only after a successful break in, and then the cam life is minutely shortened. [flat tap]
like the diff between street springs and drag race springs.
I personally have had too many instances where I'm reving the snot out of it on the street and find that the springs are rotating/carving into the spring seat slightly so I choose the drag race springs.