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Old 03-12-2004, 03:04 PM   #1
ocbaud
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fuel pump question

i have a 110gph Holley mech. fuel pump.

is there anything i need to do to make sure that the psi and the fuel delivery is good? i remember dave was having problems with his fuel pump and he had to get a regulator. this says i dont need one.
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Old 03-12-2004, 04:00 PM   #2
Captkaos
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Fuel pressure for a carb needs to be regulated down to 5-7lbs.
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Old 03-12-2004, 05:00 PM   #3
ocbaud
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thats the fuel pump i got
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Old 03-12-2004, 05:07 PM   #4
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Eric, I have mine regulated down to 4.5 -5psi and its so rich it stinks and blows fuel out the back like a smoke cloud when On it hard.

Dont know WTF is up
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Old 03-12-2004, 09:04 PM   #5
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Quote:
Originally posted by LOHRTBT

Dont know WTF is up
It's the owner who doesn't know how to tune a carb Actually Dave sounds like your floats are messed up.
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Old 03-12-2004, 09:07 PM   #6
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Quote:
Originally posted by LOHRTBT
Eric, I have mine regulated down to 4.5 -5psi and its so rich it stinks and blows fuel out the back like a smoke cloud when On it hard.

Dont know WTF is up
My friends 625cfm demon carb does that sometimes. I think it needs smaller jets in the secondaries. Probably needs smaller jets in both ends really, its basically out of the box except for putting the right secondary spring in it, which by doing that we picked up about 20 hp over whatever it had in it from the box.
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Old 03-12-2004, 09:22 PM   #7
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Quote:
Originally posted by Destructo
its basically out of the box except for putting the right secondary spring in it, which by doing that we picked up about 20 hp over whatever it had in it from the box.
Really? You mean the Vacuum secondary spring? Did you go to a heavier spring or a lighter spring? I think I need to change mine, but I don't know if I need a heavier or lighter spring. When I floor it, it seems to take a minute to REALLY get moving...
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Old 03-13-2004, 02:28 AM   #8
ocbaud
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i'm thinking of going with an edelbrock just so i wont have so much trouble keeping it tuned. i dont mind if i loose a little power by going with them. if i'm gonna want to drive it as much as i want to, i want it to be really really reliable
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Old 03-13-2004, 04:00 AM   #9
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Quote:
Originally posted by ocbaud
i'm thinking of going with an edelbrock just so i wont have so much trouble keeping it tuned. i dont mind if i loose a little power by going with them. if i'm gonna want to drive it as much as i want to, i want it to be really really reliable
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Old 03-16-2004, 11:32 PM   #10
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Quote:
Originally posted by TIMSPEED

Really? You mean the Vacuum secondary spring? Did you go to a heavier spring or a lighter spring? I think I need to change mine, but I don't know if I need a heavier or lighter spring. When I floor it, it seems to take a minute to REALLY get moving...

you need a heavier spring because you are actually feeling a flat spot during initial acceleration, because the secondaries have already begun to open and have weakened the fuel delivery signal to the primary boosters. The engine is struggling to increase speed and what you actually feel are the secondary nozzles crashing in as the engine finally reaches the speed where it provides the proper fuel delivery signal to the primary and secondary venturi. The secondaries must not open until the engine requires the additional air. This allows torque to increase along the peak torque curve. You should only feel a smooth increase in power if you have the proper secondary spring.
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