Power Valve Selection: The Definitive Answer

Just playing with this a little. There are some other programs that are better for drawing transparent colors, maybe I'll play with that some time in the future.

Blue represents fuel. White arrows show air flow from main air bleed.
This just showing how the fuel and air moves to the booster.
Ignoring the idle system flow here, and the power valve is shut.
View attachment 1715393490
Low pressure created by air flowing past the booster in a venturi draws fuel through the main jet.
Fuel moves up the main well into the angle channel and then to the booster.
At the same time, air is drawn through the main bleed by the same pressure difference.
The air passing through the upper 'emulsion' hole will pick up some fuel in the air well if its close to the hole.

As air velocity through the venturi increases, pressure difference between the booster and the atmosphere (air cleaner and bowls) increases.
More fuel moves up the main well. Standing fuel in the air well gets pulled out.
View attachment 1715393499
When the pressure difference is strong enough, the lower 'emulsion' restriction will be open to allow more into the main well from the main air bleed.



That's awesome Matt. When it's presented like you are doing, it exposes two things. How simple the Holley really is, and how much tuning you can really do if you want to.

Anything you add always makes it better.