Holley Power Valve?

General engine tech -- Drag Racing to Circle Track

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cjperformance
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Re: Holley Power Valve?

Post by cjperformance » Mon Oct 23, 2017 5:16 pm

levisnteeshirt wrote:
Mon Oct 23, 2017 4:40 pm
Go on , keep putting out bad info , and while your at it , keep moving the IFR to the bottom :) ,, i especially love that one , , if you dont know what something does , you really shouldn't comment on it ,, earth to air heads , not every carb is built to run on a delay box held wide open against a brake ,, there is circle track , and real street carbs that benefit from making a holley carb work in every facet of its capacity to give the engine what it needs at any time , ,, if you cant see that more head pressure on the main well is going to increase idle fuel ,, you really have no clue what your doing , or just stick to dynos and transbrakes
I did start to type a response to that but scrubbed it, instead I'll just add,,, far out man, what the?
Craig.

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Re: Holley Power Valve?

Post by Tuner » Mon Oct 23, 2017 7:09 pm

There are two kinds of people in this thread, those who know and one that doesn't.

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Re: Holley Power Valve?

Post by In-Tech » Wed Oct 25, 2017 6:19 am

I am not sure why I think this is perfect for this post even though it's not a binary joke.

Why do mathematicians always confuse Halloween and Christmas?
Because 31 Oct = 25 Dec. :lol:

.
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Heat is energy, energy is horsepower...but you gotta control the heat.
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Re: Holley Power Valve?

Post by In-Tech » Wed Oct 25, 2017 7:21 am

I learned the wrong way about power valve selection, not sure if it was in a holley book or where, but once I learned how to tailor PE entry and how much, there was no going back. I had to prove it to myself years ago with an o2 as well.

All the power to levi if he's making carbs work.
Heat is energy, energy is horsepower...but you gotta control the heat.
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Re: Holley Power Valve?

Post by jmarkaudio » Wed Oct 25, 2017 11:26 am

http://naca.central.cranfield.ac.uk/rep ... ort-49.pdf

Scroll to page 607, conclusion #4.
Submerged fuel metering passages are free from instability and irregularity of discharge when the head is very small.
Head is referring to the signal or pressure difference pulling the fuel. Carburetor metering characteristics were mapped out a long time ago, and at least for some carb builders forgotten, ignored, or probably most cases never researched.

I also like conclusions 1-3, They talk about the reasons using a chamfered entrance on jets rather than square edge is preferred.
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Re: Holley Power Valve?

Post by jmarkaudio » Wed Oct 25, 2017 11:59 am

levisnteeshirt wrote:
Mon Oct 23, 2017 4:40 pm
Go on , keep putting out bad info , and while your at it , keep moving the IFR to the bottom :) ,, i especially love that one , , if you dont know what something does , you really shouldn't comment on it ,, earth to air heads , not every carb is built to run on a delay box held wide open against a brake ,, there is circle track , and real street carbs that benefit from making a holley carb work in every facet of its capacity to give the engine what it needs at any time , ,, if you cant see that more head pressure on the main well is going to increase idle fuel ,, you really have no clue what your doing , or just stick to dynos and transbrakes
I agree more head pressure will push more fuel thru any of the fuel passage. However making the main jet larger or smaller or opening a PV will not change the head pressure. They will change the restriction, however since the idle feed is a much smaller restriction than the main jet that it gets its fuel from then adding a larger jet, removing it, or opening the PV won't change it. Restrictions in series will have an effect on passage flow, as long as the diameters are less then double from one to the other. in the case of the idle feed it will almost never be the case.
Mark Whitener
http://racingfuelsystems.myfunforum.org
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Good work isn't cheap and cheap work can't be good.

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