IMO....... The 077 spring is one of the worst springs ever.
Not enough seat pressure, way too much open pressure.
I actually refuse to put them on customers heads when they have shown up with them.

The 590 cam works well with 145-165 on the seat, 375-425 open, depending on what rocker ratio you'll be running and how high you plan to rev it.

For 1.5 rockers and 7000-ish rpm the Isky 8005-a installed at 1.860 is a good choice.