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  • 1 Post By blykins

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Old 08-03-2020, 03:05 PM
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Default Fuel Pressure on a 427 FE

Looking to see what electric fuel pump I would need for my 427 s/o. The engine is build for street use and has a duel quad setup with Holley 450 carbs. I'm not sure how much flow I need i a pump or how much fuel pressure this engine requires.
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Old 08-03-2020, 05:44 PM
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Default Fuel pressure

You are not going to need a large electric pump for a carb. Regardless of the pump, it would be wise to install a fuel pressure regulator and gauge on the fuel line. Holley 4150 & 4160 carbs can get a little finicky when it comes to fuel pressure. Holley recommends 5-7 psi.



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Originally Posted by cobrabritt83 View Post
Looking to see what electric fuel pump I would need for my 427 s/o. The engine is build for street use and has a duel quad setup with Holley 450 carbs. I'm not sure how much flow I need i a pump or how much fuel pressure this engine requires.

Last edited by FredG; 08-03-2020 at 05:51 PM..
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Old 08-03-2020, 11:22 PM
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Do not confuse volume with pressure. Volume is dependent on the fuel pump and lines. Pressure is dependent on the the pressure regulator.

Carburetors generally need about 5-7 PSI. Webers generally need about 3 psi. And EFI generally needs about 55-60 psi.

A 427 needs a reasonable flow, like 255 lph or so. Racing at 7,000 rpm will need a bit more. FI will also need a bit more. Doesn't matter if it has 1 carb or 4, it needs about that much fuel. If you're planning on e-85, it will need about 25% more than that. There are a number of web sites available that will help you calculate the fuel requirements.
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Old 08-04-2020, 03:34 AM
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4-5 psi is all you want.
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Old 08-04-2020, 01:30 PM
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Thanks for the help
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Old 08-13-2020, 04:43 PM
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fuel pressure at idle is one thing it's another when you're on the throttle. Thats were the volume portion mentioned earlier becomes important. You can run a gauge on it if you think it's an issue. Other wise when pressure gets too low the car will nose over as it goes dead lean.
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