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turning up fuel pressure

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Old 03-07-2012, 08:30 PM   #1
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Default turning up fuel pressure

Ok I thought I could get away with just the internaly regulated fuel pump factory set to 6.5 lbs and not have to have an external regulator. My fuel pressure guage at the carb was reading about 4.5-5lbs bouncing needle, no good.
I bought an external regulator (Holley) and I am going to turn up the
Edlebrock pump back near the tank and adjust the fuel with the external regulator. My dilema is that I cant find my paperwork for my new pump and not sure about how to crank up the pressure on the fuel pump? How do you adjust the pressure properly? I have never done this and dont want to mess up a new pump. Incidently the car starts and idles perfect right now.
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Old 03-08-2012, 01:40 PM   #2
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If you can't find the paperwork Edelbrock's website might have the information you need.

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Old 03-09-2012, 12:07 PM   #3
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Usually it is a alan head with a nut on top if it is the generic holly reg most people use. Just loosen nut a bit then turn alan head in or out to adjust pressure. Needle will still most likely bounce. A liquid filled fuel pressure gauge will help reduce that to give more accurate reading. Also have to determine if it is a return style reg or not.
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Old 03-09-2012, 12:51 PM   #4
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The only way I could increase fuel pressure on the old holley red pump i had was to change springs in the pump.
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Old 03-09-2012, 01:25 PM   #5
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This is the Edlebrock pump and I did infact find directions on there site, soo easy I turned the pump up to 6lbs at idle and when I rev it, the pressure flickers a little to around 5.5lbs. I have probably turned the fuel pump a full 2.5 turns clockwise and Im still not hitting the magical 6.5 lbs im not sure how much to keep turning the pressure adjustment screw. I messed with the Holley external regulator near the carb and It doesnt seme to make much difference in raising the fuel pressure at the carb inlet either. I was hoping to adjust the fuel pump pressure up and regulate it back down with the external regulator and therefore eliminate the needle flickering and achieve a consistant 6.5 lbs at idle and while revving engine.

Originally Posted by newschool72 View Post
The only way I could increase fuel pressure on the old holley red pump i had was to change springs in the pump.
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Old 03-09-2012, 01:54 PM   #6
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Aside from lacking your desired pressure, it sounds like a typical dead head regulator setup with the pressure drop.

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adjustment, electric, external, fuel, holley, lq9, pressure, pump, red, regulator, screw, swap, turn, turning, uo

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