Holley 2bbl Fuel Pressure?

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Winchester_Black

Winchester_Black

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Hey Super Six folks, I’m running a 2bbl 225 with a 350cfm Street Avenger. I have a ‘72 Cali original model with fuel tank return line so I’m running a 3-way filter.. still have a little too much fuel pressure so I’m installing a fuel pressure regulator and gauge next week.. anyone running a similar setup that can share what fuel pressure they are running?
I think I can adjust from 5-10psi
 
What do you call too much pressure?
 
I'm wondering too. How did you determine that it's too high?

Years ago, an engineer who started Product Engineering, which Magna Fuel has since bought out, and began using some of his proprietary designs, told me that about 3 out of 10 Holley needle and seats will tolerate up to 11 psi of fuel pressure. You just have to go through and test them individually to find out which 3.

I found it to be true when tuning on my 3-2bbls.

20200427_174153 (Medium).jpg
 
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Rug_Trucker said:
It won't let the needle valve seat due too the pressure...............fuel blows out of the vents
Click to expand...
The float might be bad. Needle and seat could be bad too. Might have trash in it. You can't tell by guessin and that's what you're doing. You might be right. But you might not be.
 
Rug_Trucker said:
It won't let the needle valve seat due too the pressure...............fuel blows out of the vents
Click to expand...
Holley says 6.5 psi if memory serves. Are you using the 3 nipple fuel filter with the metered orifice? How big is your return line? You may be able to run an bypass style regulator.
 
Rug_Trucker said:
It won't let the needle valve seat due too the pressure...............fuel blows out of the vents
Click to expand...
That could also mean you've got junk in the bowls blocking the needle valve or a sunken float.
Are you running a mechanical or electric pump?
 
RustyRatRod said:
The float might be bad. Needle and seat could be bad too.
Click to expand...
Rug_Trucker said:
It won't let the needle valve seat due too the pressure...............fuel blows out of the vents
Click to expand...
Yes, fuel coming out of vents. Float is moving freely and everything else seems to work correctly.
Mechanical pump is only making 7-7.5 psi based on the readout from a spectre performance gauge, so junk in the needle seat would make sense, but fuel tank, pump, filter, lines and carb are all new, so I didn’t expect that.
Can dial it down to 5 psi. Will do so and report back. Maybe try to come back up to 6-6.5 from there if all is good.
 
Winchester_Black said:
Hey Super Six folks, I’m running a 2bbl 225 with a 350cfm Street Avenger. I have a ‘72 Cali original model with fuel tank return line so I’m running a 3-way filter
Click to expand...

Pay careful attention to how you have that fuel tank vent system configured and hooked up; see here for how to do it correctly.

Winchester_Black said:
.. still have a little too much fuel pressure so I’m installing a fuel pressure regulator and gauge next week.. anyone running a similar setup that can share what fuel pressure they are running?
I think I can adjust from 5-10psi
Click to expand...

The stock Slant-6 pressure of 3 to 5 psi will be plenty.

The 500cfm will be a good bit more than plenty, if your engine is more-or-less near stockish.
 
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slantsixdan said:
Pay careful attention to how you have that fuel tank vent system configured and hooked up; see here for how to do it correctly.



The stock Slant-6 pressure of 3 to 5 psi will be plenty.

The 500cfm will be a good bit more than plenty, if your engine is more-or-less near stockish.
Click to expand...
Thanks Dan, can you send me that url? I wasn’t able to see the link..
 
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