Fuel System Questions for a Gen III Hemi Swap - Built 6.1

Aron

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Hey B Body Fans,
I've got some (total rookie) questions about building my fuel system for a Gen 3 Hemi Swap in a 1968 Dodge Charger. The specs on the motor are a built out 6.1 Gen 3 Hemi, NON VVT, likely will make between 550 to 600 hp, built by BES Racing shop.
The car is stripped to metal, now in epoxy and I'm mocking it all in before removing it all, then to paint and body. I'm learning as I go.

Here are my fuel system questions, starting at the gas tank (from Tanks Inc.) and working my way forwards:
1) I have the fuel pump Tanks Inc. gave me, 340lph, but may buy one from Red Horse Performance as I've heard not so great things about the Tanks Inc. ones.
2) In terms of line size, my tentative plan is to start at AN-8 at the back and run both sending and return lines forward to...
a) Is AN-8 the right size or should I go AN-6?
3) Connecting the sending line to the 6" fuel filter, AN-8 (or AN-6?), also from Red Horse Performance, with a 10 micron filter
4) Now...here is where I'm confused...does it go like this??
1668482447945.png


5) And the filter goes between the tank and the regulator right? Or is this all wrong?
--> Meaning, that the sequence is: Tank --> Filter --> Regulator (3 inlets, bottom being return back to tank) --> send it to "1st" fuel rail (side matter?) --> Then tube to "2nd" fuel rail : STOP
6) And from reading around, looks like the ideal pressure is 58.5psi

Somebody educate me....Thanks all, Love this forum and all of your help to date has been amazing.

-Aron

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70chall440

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You are going to get several opinions here but here is how I do it and what I recommend.

1. The line size can be -6 (3/8) although I have no doubt some will recommend -8 (1/2), there is a lot of discussion around this issue but IMO it is all about the pump more than the line. Regardless of the size, use quality stuff, this is not the place to go cheap.

2. I run the feed line from the tank/pump up to a filter, then up to one fuel rail, from one fuel rail there is a line to the other rail, from there the line goes to the regulator, then from the regulator back to the tank (aka return line).

3. The pressure depends on the rails and injectors but 58 (ish) sounds right.
 

diesel_lv

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-6, 3/8", will supply 700hp no problem. You have 2 options,
1: run feed from tank to regulator then to 10 micron filter then to fuel rail on engine, with return line returning immediately from regulator to tank.
2: run feed to 10 micron filter then to fuel rail at engine and return from fuel rail to regulator close to engine then to return in tank.
Either way, use 3/8 factory line with a tube to AN adapter on both ends.
Issue w #1 is some fuel pumps and regulators cause a pulsing/hammering effect deadheading and some are just fine. #2 requires a little more plumbing but no issues of "possible" pulsing.
 

Sixpactogo

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I have a 6.1 in my 68 Charger. I used your plan with the AN-6 fittings as shown in Aeromotive Inc. design for fuel injected OEM in post 4. My 6.1 seems to prefer just under 58 psi but my engine is stock except for a larger throttle body and a Diablo tune. I am using the pump that came in my tank and have not had any issues since 2015. You are on the right track IMO and you will be happy with your build. I mounted the filter on the frame rail just behind the right front wheel and the regulator near the engine. Here is a pic of my engine compartment.

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Aron

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Outstanding, thank you all. This is incredibly helpful. Given the consensus, I'll go with AN-6 and work from there.
Thank you all, very much appreciated, as always.

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Aron

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Hey Sixpacktogo, first, beautiful car - and engine bay, it's gorgeous!

Second, just to be clear, you went with this set up (except you plumbed into the back of one of the two fuel rails, and there is only one line between the fuel rails?):
1668529645311.png


Thanks again!
 

Sixpactogo

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Hey Sixpacktogo, first, beautiful car - and engine bay, it's gorgeous!

Second, just to be clear, you went with this set up (except you plumbed into the back of one of the two fuel rails, and there is only one line between the fuel rails?):
View attachment 1373581

Thanks again!
Thanks Aron. Yes only one line between the rails. Another difference from the Aeromotive diagram is I have a 5/16" return line from the regulator to the tank because that is the way my tank was set up. (3/8 out 5/16" return) The fuel rails are the stock pieces that came on the 06 Charger the engine came from. I figured if it was good enough for that 06 SRT8 it would be good enough for me. Good luck with your build. It is shaping up nicely.
 
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