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11 PSI fuel pressure at the carb

Houle #382

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Need some advice, 440 30 over aluminum heads Edelbrock performer RPM intake 800 AVS2 and a hydraulic roller cam, fuel pressure gauge reads 11 psi, thought it could be a faulty gauge so I bought another gauge still reads 11 psi. I called Edelbrock and talked to a tech, he said I have 2 options purchase the Edelbrock fuel pump (1723) $200 bucks which he said is designed to run no more than 6 PSI or a fuel regulator 8190 $141 bucks. I decided to go with the fuel pump as I try to keep the engine compartment clean, if I run a regulator then I have to mount it somewhere and run line. Anyway bought the pump got it installed started it up 11 PSI what the frick. I'm lost even a couple of buddies don't have an answer, there is no electric fuel pump just the mechanical pump. Going to try a 650 AVS2 tomorrow but don't think it's going to make a difference, put on the thinking hats !
 
I can speak from experience on the edelbrock fuel pump it will put out more than 6 psi the one on my hemi makes 8 psi so a regulator is really the best bet.
 
What was your first pump? Seems odd two doing the same. Is it flooding?
 
What gauge? Is it some cheap pressure gauge? Does the fuel just pour into the venturis? Does the motor run ok? Carter/Edelbrock usually require 3 to 6 psi on fuel pressure, but I am not sure about the avs2 carbs. If it is not flooding and runs fine, my money is on inaccurate pressure gauges.
 
Need some advice, 440 30 over aluminum heads Edelbrock performer RPM intake 800 AVS2 and a hydraulic roller cam, fuel pressure gauge reads 11 psi, thought it could be a faulty gauge so I bought another gauge still reads 11 psi. I called Edelbrock and talked to a tech, he said I have 2 options purchase the Edelbrock fuel pump (1723) $200 bucks which he said is designed to run no more than 6 PSI or a fuel regulator 8190 $141 bucks. I decided to go with the fuel pump as I try to keep the engine compartment clean, if I run a regulator then I have to mount it somewhere and run line. Anyway bought the pump got it installed started it up 11 PSI what the frick. I'm lost even a couple of buddies don't have an answer, there is no electric fuel pump just the mechanical pump. Going to try a 650 AVS2 tomorrow but don't think it's going to make a difference, put on the thinking hats !
Regulate it down to about 5 or less. Don't rely on a pump to regulate the pressure.
 
What was your first pump? Seems odd two doing the same. Is it flooding?
I put a new Carter pump ( M6903 super street ) on last year that's designed for 5.5 to 7.5 PSI and that was running 11 psi, this is what's really strange it's not flooding out or running rich, the car actually runs really good but the 11 PSI has me worried.
 
Lots of the carter/edelbrock mechanical pumps are coming through with too heavy of a spring creating too much pressure. Even the ones that supposed to be less pressure.
 
What gauge? Is it some cheap pressure gauge? Does the fuel just pour into the venturis? Does the motor run ok? Carter/Edelbrock usually require 3 to 6 psi on fuel pressure, but I am not sure about the avs2 carbs. If it is not flooding and runs fine, my money is on inaccurate pressure gauges.
Bought a new really good gauge and that was reading the same 11psi, not sure about fuel just pouring into the venturis as they don't have the down leg like other Edelbrock carbs it doesn't run rich at idle. The new AVS2 carbs say 6.5 max psi
 
I put a new Carter pump ( M6903 super street ) on last year that's designed for 5.5 to 7.5 PSI and that was running 11 psi, this is what's really strange it's not flooding out or running rich, the car actually runs really good but the 11 PSI has me worried.

IIRC there's been heavier float needles that will withstand a little more pressure but not a lot. My two 600s were doing okay for awhile with 8 lbs. Then I started having more carburetor bleed downs after shutdown. Had my fuel pump redone by @Mike-Casella at Then and Now. Been doing okay so far.
Mechanical Fuel Pump 101
 
I plan on calling Edelbrock again tomorrow, I have the Techs name that I spoke to on Monday

Edelbrock was having Carter specially make their pumps to Edelbrock's specks. (Lighter spring). You kind of know how that works out all the time with the over seas manufacturing.
 
Some gauges have a plug you have to pull out
 
Lot of cheap two port regulators on the market.
Holley and a dozen knock offs.
They are a very simple part and pretty trouble free
and easy to adjust.
 
Need some advice, 440 30 over aluminum heads Edelbrock performer RPM intake 800 AVS2 and a hydraulic roller cam, fuel pressure gauge reads 11 psi, thought it could be a faulty gauge so I bought another gauge still reads 11 psi. I called Edelbrock and talked to a tech, he said I have 2 options purchase the Edelbrock fuel pump (1723) $200 bucks which he said is designed to run no more than 6 PSI or a fuel regulator 8190 $141 bucks. I decided to go with the fuel pump as I try to keep the engine compartment clean, if I run a regulator then I have to mount it somewhere and run line. Anyway bought the pump got it installed started it up 11 PSI what the frick. I'm lost even a couple of buddies don't have an answer, there is no electric fuel pump just the mechanical pump. Going to try a 650 AVS2 tomorrow but don't think it's going to make a difference, put on the thinking hats !
Run a stock over the counter pump, they're designed to run at that pressure and the price tag isn't influenced by a name....IMO. You never mentioned what your application is.. Street, strip, slalom or all race? If your just knocking around the street with the occasional "exhibition of speed" a stock pump will suffice.
 
I have a Carter M6903 on each of my 2 cars. Both had 11 lbs plus pressure. Caused me carb issues. I ordered kits for rebuild from a company called Then And Now Automotive. Fixed the problem. Now 6 psi. The spring is much lighter. Another thing to consider is that I lost both fuel pump push rods - is this related to more fuel pump rod pressure? Not sure, but something to consider.
 
Need some advice, 440 30 over aluminum heads Edelbrock performer RPM intake 800 AVS2 and a hydraulic roller cam, fuel pressure gauge reads 11 psi, thought it could be a faulty gauge so I bought another gauge still reads 11 psi. I called Edelbrock and talked to a tech, he said I have 2 options purchase the Edelbrock fuel pump (1723) $200 bucks which he said is designed to run no more than 6 PSI or a fuel regulator 8190 $141 bucks. I decided to go with the fuel pump as I try to keep the engine compartment clean, if I run a regulator then I have to mount it somewhere and run line. Anyway bought the pump got it installed started it up 11 PSI what the frick. I'm lost even a couple of buddies don't have an answer, there is no electric fuel pump just the mechanical pump. Going to try a 650 AVS2 tomorrow but don't think it's going to make a difference, put on the thinking hats !
Issue resolved, I tried two different gauges both showed 11 psi, I decided to stop at a speed shop and bought one of their gauges, put it on started the car up 9psi a little better. Pulled the Edelbrock pump and put my original pump on which I have no idea who's it is, the guy I bought the car from in 2012 had the engine rebuilt in 2000 so whatever one they bought and put on the engine that's what I put back on. Started the car up 7psi, took the car for a ride got back home popped the hood and gauge showed 6 psi. Edelbrock pump is on its way back to Summit.
 
I have not had an edelbrock open to compare the springs to stock hemi and the early orig carters. Hard to believe they can't spec it right. Unless the manufacture had a bunch of non related springs they decided to use.
 
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