Fuel pressure regulator plumbing?

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Cope

Cope

Fusing with fire
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Just got the dart running and went out for a drive. My fuel pressure is way to low, like 2.5 Lbs. Not sure if my regulator is bad or if I have it plumbed wrong?
I have the regulator adjusted all the way up. (Screw turned all the way in per instructions.) And it's still not over 3 psi?

Pump is summit eletric and new.

20180824_135119_zps125txi45.jpg


Bottom -8 line is fuel in.
Left side -6 is fuel to the Y block.
Right side -6 is return line.

I thought both sides labeled our
would be regulated but it seems like it's just pumping right back into the tank?

The regulator is a cheep Holley one.

Did I screw up the plumbing or should I get another regulator?

Thanks.
 
dont get mad...but are you sure it is return style regulator?

it looks like it might be a regular one, and the right side is basically an open loop back into the tank
 
No I'm not sure. It does say both sides can be used as feeds for a dual inlet carb, so I figured both outlets would be regulated?
 
Cope said:
No I'm not sure. It does say both sides can be used as feeds for a dual inlet carb, so I figured both outlets would be regulated?
Click to expand...
which means you have 8 PSI going out both sides...which is fine if both are plumbed to a carburetor
in your case, one is plumbed to a carburetor, the other to an open line
the fuel will take the path of least resistance, which is right back into the tank

try this, just for fun, take the return line off and plug the hole
my guess is you will see more then 8 PSI at the carbs


the way to fix this, is to put a restriction in the return line, like some of the stock hemi filters had...i think it is a 30 thousands hole
 
I'm with diy in that that regulator isn't a return stupyle regulator. Why do you want to bypass with that system?

You can do a diy says and restrict the return line but IMO you are better off feeding one side of the regulator to each carb and not returning fuel.

If you are going to return fuel you need to make sure you have about 15-18 psi in the number 8 line to the regulator or it will run out of fuel.
 
I want a return so I'm always getting cool fuel and not running hot gas.
 
I understand the cooler fuel but I have to agree that's not a return type regulator, nice thing is atleast you have the return line there just swap regulators for a return one and plumb both sides to the each carb. One like this, not saying you have to go automotive.

AEI-13301.jpg
 
Cope said:
I want a return so I'm always getting cool fuel and not running hot gas.
Click to expand...


That's good, but you can't have an open line back to the tank then. You have to restrict it down, otherwise, fuel will damn sure head back to the tank rather than to the needle and seats.

Fuel, like electricity is lazy and will ALWAYS take the path of least resistance.

Soooooooooooooo that means you need to make a restricter for that return line. Once you do that, you SHOULD be able to use the regulator to set pressure.
 
My first bypass system didn't even have a regulator. I used a Hilborne #8 high speed bypass and set the pressure with that.


Worked like jack the bear, fuel pressure was dead consistent and, I could run 35 pounds of line pressure.
 
I was just looking on summit, a return style are all 150 bucks or so....
I may just stuff a carb jet in the braided line...

:)

(Gotta save cash for my new trany build and converter.)
 
Last edited:
Cooler gas is cool... i guess.
I went from a deadheaded deal( Holley black) to a big return style fuel system on a weekly raced 9 sec car and didnt see absolutely anything in ET difference.
I dont know how much if at all the fuel was cooler with the fancy return system, but it sure didnt make a lick more power.
I would spend money elsewhere
 
if that is a holley regulator. 803...screw it up reduces the pressure....just installed new regulator on a Duster....instructions said to turn clockwise to increase pressure...and they are preset at 6 psi....which is what mind showed on start up...


The regulator comes from Holley with the regulator pressure preset (see table). However, for individual requirements, it may be readjusted. Loosening the regulator locknut and turning the adjustment screw clockwise increases the pressure. Decrease pressure by turning the adjustment screw counter-clockwise.
 
70aarcuda said:
if that is a holley regulator. 803...screw it up reduces the pressure....just installed new regulator on a Duster....instructions said to turn clockwise to increase pressure...and they are preset at 6 psi....which is what mind showed on start up...


The regulator comes from Holley with the regulator pressure preset (see table). However, for individual requirements, it may be readjusted. Loosening the regulator locknut and turning the adjustment screw clockwise increases the pressure. Decrease pressure by turning the adjustment screw counter-clockwise.
Click to expand...

he got it right, he said he cranked the pressure UP by turning the screw DOWN
(i had to read it a few times myself before i got it)
 
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