Holley Power Valve Experimentation

Definitely a vehicle that sees street action. If you drove two identical vehicles: one with a “Holley method” of 1/2 of idle vacuum and the other one done by 1/2 of cruise vacuum you would see immediately which is the correct method. Most obvious realization would be at various part throttle (primaries only) operation. But you can’t just slap in a higher number PV and roll. You have to tune all the circuits, one at a time in correct sequence. Seeing/feeling is believing.
I go a bit more than half cruise vacuum. Mine for instance is 14hg at cruise. So I want about 2 under that. But the 10.5 is all that's available. It does make a big difference too. You're right on the money about that.