LS EFI fuel plumbing

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Rich Andrews
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LS EFI fuel plumbing

Post by Rich Andrews »

Ok, so I am going to be hooking up a full flow system which requires a return line to the gas tank.

Anyone doing this, and should i worry about the return gas dripping into the tank and creating bubbles?

I do have a return and vent so Im thinking it wont be a problem.

I also saw the MFG like to run the regulator on the return side for a full flow set up, am I ok on the intake side after my filter/pump/filter which is a dead head style?
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Dockside Dave
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Re: LS EFI fuel plumbing

Post by Dockside Dave »

Typical on LS. Do you need pics? My Bosch pump in actually in the tank.

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Aeon
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Re: LS EFI fuel plumbing

Post by Aeon »

Pickup to pre filter and pump mounted below tank. Post filter to regulator then one line back to tank and one to rail
17x8 Circle H powered by a TurnKey LS3, 2.55 ox box and 82" 3 blade JX

Gladesman06
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Re: LS EFI fuel plumbing

Post by Gladesman06 »

I can tell you from experience if your return line doesn't return toward the bottom of the tank you will have a huge problem with the fuel foam/aerating. You might not notice it when the tank is full but you can really tell once you get down to about a half tank. The thing is the return line doesn't just trickle back to the tank, it's returning at a pretty high rate. I've run my regulator both ways and didn't notice a difference either way. I now run 100 micron filter before the pump and a 40 micron after the pump. Then from there it goes to my regulator. It works perfectly this way. The fuel pressure stays consistent and the fuel stays cool.

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Prototype
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Re: LS EFI fuel plumbing

Post by Prototype »

I'm lost?
Are you returning gas or diesel?
Diesel foams like a MF from certain stations but, Gas?
Dump the return on top, no dipper tube, unless you need aerated fuel!
Dawn is not a gas additive no matter what you hear about foaming tanks!
I would not down size the return line though as some do? That could spray your tank internally with some not so good fittings!

Aeon
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Re: LS EFI fuel plumbing

Post by Aeon »

My return is on top and no foam here
17x8 Circle H powered by a TurnKey LS3, 2.55 ox box and 82" 3 blade JX

Gladesman06
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Re: LS EFI fuel plumbing

Post by Gladesman06 »

Prototype pretty much every comment I've seen you post on here it has shown that you seem to always be lost so nothing new there Sir.

Rich Andrews
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Re: LS EFI fuel plumbing

Post by Rich Andrews »

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Gladesman06
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Re: LS EFI fuel plumbing

Post by Gladesman06 »

Thank you for posting that Rich. It is a very common problem and is over looked a lot. When you buy a return style system they make a huge note of how to make sure you plumb the return line but for some reason people still do it wrong. They must have clearly put Dawn dish soap in with the mineral spirits when they were doing this video. I guess it only matters if you are using diesel fuel or Dawn dish soap LoL.

Rich Andrews
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Re: LS EFI fuel plumbing

Post by Rich Andrews »

Ya... ha ha. I did find out my return side of the tank does have a baffle and my pick up is on the opposite side so I should be good. But that video is pretty spot on and probably the root cause of lots of issues people have. Im learning all this new LS stuff so appreciate the replies.
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Gladesman06
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Re: LS EFI fuel plumbing

Post by Gladesman06 »

Awesome news. Yes you should be perfectly fine with it set up that way. It's all a learning game but if you aren't learn then you ain't living.

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