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Discussion Starter #1
hey guys.
I just replaced the external reciprocating electric fuel pump with a rotary pump on my 67 super with a 2 liter and weber 45s. I bought a pressure regulator to pull the pressure down to 5 lbs because I had heard that that was the correct fuel presure for carbs.

Long story short, the car would barely run and died under a load. So after pulling the line off and testing the volume of fuel coming out, I decided to try without the regulator. Lo and behold it runs fine, but if I give it full throttle all at once it acts like it needs more fuel.
I have 2 questions:

1. What is the correct fuel pressure for weber 45mm
2. What sort of fuel volume should be coming from the line when the fuel pump is on? (I measure it by removing the line from the carbs into a container for 10 seconds while the engine is off)
 

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The short answer is 3 - 5 psi. I doubt a 2 L @ full throttle can initially use more fuel than an oz or two, thus volume is not the likely problem. The original FISPA FRB11 regulator was to keep the pump pulses from hammering the needle valve into a depression in the brass float. (1) check float leval. (2) check float drop. (3) check float freedom of movement on axle. If your pump jets delivered enough volume with the old set up, check to see if there is a problem in the pump circut or the jets themselves after the addition of the new fuel pump. It is likely your problem is in this area.
Gordon Raymond
 

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Discussion Starter #3
Did some research in the archives last night and ended up purchasing and installing a Carter 4070 fuel pump today. It was a bit of a PITA because it didn't fit in the location that the old pump did. The problem seems to be solved:D

Gordon, thank you for the suggestions.:) I will try checking those things anyway because I feel that they probably need to be gone through. It seems that most of the things on this car were monkied with at one time or another:(
 
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