Fuel Pressure on a 427 FE

[cobrabritt83]

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.

[FredG]

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.



Fred

Originally Posted by cobrabritt83

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.

[bobcowan]

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.

[blykins]

4-5 psi is all you want.

[cobrabritt83]

Thanks for the help

[maui]

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.