Fuel Pressure at Carb?

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Ol Yeller
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Fuel Pressure at Carb?

Post by Ol Yeller »

I apologize in advance and know this topic has probably already been covered, but my question is: Is 4 psi. of gas at the intake of a Holly 600 double pumper enough? My Holly Blue is rated at about 13 psi. at the outlet but after traveling up 4 or 5 feet and going through a fuel regulator, it's 4 psi at the carb. If it's not enough, is it fairly straightforward to adjust the regulator or am I opening a can of worms?
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HomesteadGator
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Re: Fuel Pressure at Carb?

Post by HomesteadGator »

Recommended fuel pressure should be set at 7-1/2 psi maximum; 5 psi minimum. Fuel pressures above 7-1/2 psi can
create severe fuel control problems and are not recommended.

I pulled this off of the Holley website on the 1st page under general information. Hope you get her runnin good!
http://www.holley.com/data/Products/Tec ... 65rev1.pdf
FTD RACING
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junglecat
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Re: Fuel Pressure at Carb?

Post by junglecat »

Its pretty straightforward just adjust regulator till you have around 7psi at carb.
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Ol Yeller
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Re: Fuel Pressure at Carb?

Post by Ol Yeller »

Thanks for the advice. I needed a little hand holding because lately I've been through fuel pump hell. But the regulator adjusted just as advertised and I put her to 6.5 psi. Actually the engine ran good at 4 before but if it should be between 6 and 7, then that's where I'll keep her. Thanks again.
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Ol Yeller
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Re: Fuel Pressure at Carb?

Post by Ol Yeller »

I set it a little low to stay away from the 7.5 max.
scottymartin
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Re: Fuel Pressure at Carb?

Post by scottymartin »

I burnt up an O-360. To much fuel pressure at the carb, pump wouldn't shut off...
It belched and away we went !!
Pressure was to high for carb.
It is important...
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southernrican
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Re: Fuel Pressure at Carb?

Post by southernrican »

Ya I have mine set at 6.5 lbs. also need to check bowls and needle a d sets make sure there working properly in some extreme cases of to much fuel pressure your needle and seat will bleed by.
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juice
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Re: Fuel Pressure at Carb?

Post by juice »

6 to7 lbs and you should be good I went to the similar problem at 1 time 7lbs is good. Don't go higher
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