Fuel hose AN6 or AN8

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I would use -8 front to rear. It can drop to -6 after the regulator at the carb. -6 is smaller than 3/8" ID. The hose ends are even smaller than the hose depending on whose you buy.

And I would use a better pump. Those little Holleys use 3/8NPT fittings - small IDs again. Or use two of them plumbed parallel on separate switches. Ride around on one, use both when you go racing. Plus you have one to get you home when one breaks.

Using a good pump that makes some line pressure will serve to keep it from boiling or vapor locking.
Did you install a check valve on the output of each pump?
 
Here is a diagram of my dead head system, I run on the street and strip with zero problems.
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Did you install a check valve on the output of each pump?

No. I have the same set up on another guy's car - twin feeds, filters and 2 Holley Blue pumps feeding a -10 to the front. I keep telling him to take those pumps off and put something decent on, but he says they're fine. Big Block Chubby, 9.40s in a 3300# car.
 
H
Oh **** are most of you guys running a return
The main reason for a return after the carb is to keep the cold fuel flowing past the carb. if it dead ends at the carb the new ethanol fuel will boil and cause a rich mixture from the needle and seat not working properly from the floats not shutting the fuel off. I first noticed this when I would go to restart the car when hot after shutting it off and letting it sit a couple minutes. I also noticed the AFR was better before the 60 ft. wit the return. Depending on the temp of the car it was always changing . You won't have to rev the car on the line to clean it out before prestage when you have a return.

You can never have to big of a fuel line. But you can have to small. One time front to back was $200. I really didn't want to spend the other $200 but Tony Hirschman talked me into it. Glad he did. I also threw my other regulator in the tool box and bought two return style . Got to have a spare he said!

If you cannot afford a return you can try taking the hood off. Here are pics of before and after

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I never used a return style regulator in 45 years of racing and I’ve been 8.42@160mph. Why do you feel they are needed.
I didn't either. Most all 80's carbureted cars came with a return? They added the upgraded filter and a return line. I could not believe the difference. Tap the key through the window and it fired right up any time.

Note the return on this filter . You see it on many 80's mopars.
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First return I ever encountered was the factory setup on my 70 440-6. It came on some earlier cars, hemis, as well. THEY WORK. Most of the time I had that car with a 440 in, was in San Diego in the Navy
 
I've never run a return system. However, I like the idea, I've installed some, I think there are advantages and the next one I do on something I own will probably be a return deal.

On a non-return system, fuel is deadheaded at the regulator(s). On a return system, it's constantly flowing in a big loop, with whatever is not being used at the engine being returned to the tank.
1) Not deadheading the pump takes the load off of it, runs free, runs cooler, lasts longer.
2) Fuel laying in the line under pressure doesn't have to "get moving" at the hit, it's already moving.
3) Fuel at the engine stays cooler and consistant in temperature and pressure.
 
Oldmanmopar, in the second picture, did you install the bypass regulator after or before the carbs?
 
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With my BG400 pumps I run a return from the fuel pump in back of the car and dump into the top of my fuel cell. I built a tube so the fuel enters under the fuel near the bottom so it doesn’t make bubbles.
Can you post a picture of that set up? Or a diagram. I am imagining it dead heads at the carb?
 
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Can you post a picture of that set up? Or a diagram. I am imagining it dead heads at the carb?


I’m guessing you want a picture of the regulator to the carb. Sorry it’s not very pretty but here it is. This is on my black Duster. BG400 pump in rear, return from pump to top of tank, number 10 line to regulator and 8 to carb
 
Can you post a picture of the pump in the rear where it returns from pump to top of the tank if possible?
I assume that is a deadhead regulator.

since my aeromotive pump has an inlet and outlet port, can I just run a line from the outlet port to the top of the tank?
 
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Can you post a picture of the pump in the rear where it returns from pump to top of the tank if possible?
I assume that is a deadhead regulator.

since my aeromotive pump has an inlet and outlet port, can I just run a line from the outlet port to the top of the tank?



Im back in the house now and honestly with it on the ground I couldn’t get a good photo but check out the link. The picture is how I’m plumbed in the back.


Barry Grant BG 400 Installation And Tuning Instructions (Page 3 of 4) | ManualsLib
 
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