62Ranchero200
Famous Member
Greetings Ford Six Fans,
This may be a stupid question...
As I understand it, the spring on a Holley power valve (such as on a Holley 4412, "500 CFM" 2 BBL) is always trying to open the PV, and engine vacuum holds the PV closed. For example, if my engine idles at 11" of vacuum and I have a #55 PV, the PV should open when engine vacuum falls to 5.5".
So far so good?
If that's the case, shouldn't be PV open and remain open when the engine is shut off? Wouldn't that cause a continuous fuel leak until the fuel bowl was drained?
Thanks
Bob
This may be a stupid question...
As I understand it, the spring on a Holley power valve (such as on a Holley 4412, "500 CFM" 2 BBL) is always trying to open the PV, and engine vacuum holds the PV closed. For example, if my engine idles at 11" of vacuum and I have a #55 PV, the PV should open when engine vacuum falls to 5.5".
So far so good?
If that's the case, shouldn't be PV open and remain open when the engine is shut off? Wouldn't that cause a continuous fuel leak until the fuel bowl was drained?
Thanks
Bob