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Discussion Starter #1
Hey guys, I was at the hose/fitting store today picking something up and it came to my attention that the guy I seemed to always deal with got fired for general incompetence. I should have checked on my own and not taken his word for it but turns out the hose he sold me for inside my gas tank isn't submersible. Now I'm having a hard time finding 1/2" I'd hose that is both submersible and can handle fuel injection pressure.

I'm merging two 3/8" Lines from walbro 255s through a y to a single 1/2" line inside the tank. I know the pressure at the regulator will only be 50ish psi but I'm not certain what kind of spikes I could get since I'm merging two lines together.

I called a parts store and they said they had some but when I got there the hose only had a working pressure of 35psi. I'm sure they under rate the stuff but I don't really want to experiment since it's going in the gas tank. I know all kinds of people merge multiple lines in the tank using AN fittings and what not, so what are they doing? All the braided line I found isn't submersible.

Anyone got a lead on where I can find some high pressure, submersible 1/2" ID hose? I only need a foot.

Thx
 

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You aren't going to find 1/2" submersible hose that fits your needs, the best stuff out there right now comes in 3/8" and 5/16". For the amount of power you can make with a pair of 255s you should be fine joining the 3/8" lines together to 3/8" inside the tank, and running -6an or larger outside the tank. I just put together a car with twin 465s making 800whp on e85 with all 3/8"/-6an, seeing a max of about 70psi with no issues whatsoever. I have the pumps staged to keep them from working too hard out of boost.
Cheers,
- Jon
 

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Discussion Starter #4
I already have the barbed 1/2 Id fitting welded to the sending unit so I don't want to redo it. I'm thinking I'll butt my 1/2 y fitting right up to my 1/2 barb fitting so the hose will literally only be acting as a coupler between the two fittings. Then I'll clamp the piss out of it. This way I can use the submersible hose as well. What I don't get is when you google duel fuel pumps. Probably 50% of the pictures are braided line. Even on this forum I've seen many people using braided in the tank and I haven't seen a single issue come of it as of yet. Has anyone actually seen this fail personally? Or is always a friend of a friends cousins uncles sisters Co workers type of situation?
 

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You're going to have to order that hose from summit or a similar site and it's not cheap. I know Dayco makes it. I recently bought some.

Braided lines are not made to be submerged. You can get away with it just like you can get away with using non submersible rubber line but it's not the correct part for the job.
 

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Discussion Starter #6
Ya I checked Dayco's website and they only show up to a maximum of 3/8 in submersible fuel injection hose.
 

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Ya I checked Dayco's website and they only show up to a maximum of 3/8 in submersible fuel injection hose.
Yeah. 3/8 is probably going to be the limit on submersible. You can refer to the following post about 1/2. Supposedly these guys use some 1/2 hose in-tank but it's not officially rated for it. Use at your own risk obviously...

http://ck5.com/forums/threads/need-some-1-2-id-submersible-fuel-line.305386/

They make dual 3/8 to 1/2 barb fittings. Depending on how much room you have that might work?
 

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Discussion Starter #8
Ya I already have the 3/8x2 to 1/2 barb. I know this is likely overkill, most people who run duel pumps just merge the two 3/8 lines to a single 3/8 then to whatever they want when it gets out of the tank but I like to be complicated I guess. I just don't like the idea of putting additional stress on the pumps or having a blockage that restricts flow. If I could do it all again, I'd probably run a separate feed line.

Anyway here is a diagram. On the left is what I have currently, on the right is what I'm thinking so I can minimize the not properly rated hose. The debate is do I use braided line which "supposedly" can't be submerged (even tho people do it all the time) but can handle the pressure or do I go with the 1/2" stuff I got that can be submerged but is only rated to 35psi. I'd run hose clamps up the entire length if I used the low pressure. That being said if I butt the two barbs together the barbs should be the ones exposed to 99% of the pressure.

 

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Don't use the 35PSI line. That's definitely not going to work. I would go braided before I did that. I have dual 6AN feeds and a single 6AN return on mine. Works fine with base pressure of 50. I want to stage the pumps later this year as I'm certain I'm overheating the fuel but it does work. Why not just tap your hanger for a second 3/8 feed and either combine them outside (which is common) or run dual feeds the whole way (also common)
 

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Discussion Starter #10
Because I've already got a 1/2 barbed inside the tank to - 8 welded to the top. And I also already have a - 8 line run through the car to the rail and the return done for a single - 8 line.
 

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Because I've already got a 1/2 barbed inside the tank to - 8 welded to the top. And I also already have a - 8 line run through the car to the rail and the return done for a single - 8 line.
I don't understand why people overcomplicate it with the "Y" fittings. Just use your existing -8 line as one feed and the factory feed as the other line. You would actually be simplifying your setup.
 

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Discussion Starter #12
Ya you know what after taking the pumps back out tonight and putting it on the bench. I'm just going with the running 2" of braided hose method. It's so far up at the top of the tank this way it wouldn't even be submerged.
 
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