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Old 07-31-2019, 11:24 AM   #26
weedoublewide
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Re: LS bypass fuel pressure regulator question

Does it matter what size line is used for the return back to the tank?
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Old 07-31-2019, 06:21 PM   #27
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Re: LS bypass fuel pressure regulator question

Usually its 5/16 to match the return size on the rail, or the filter/regulator.
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Old 08-06-2019, 10:28 PM   #28
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Re: LS bypass fuel pressure regulator question

Got it, and what pressure can we expect to see on the return line?



Thanks,

double
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Old 08-07-2019, 02:18 AM   #29
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Re: LS bypass fuel pressure regulator question

There's no real way to measure it, but it wont be much, its low pressure on the return.
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Old 08-07-2019, 06:00 AM   #30
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Re: LS bypass fuel pressure regulator question

Agreed with ls1nova...the return is free flow with no head pressure to the tank...
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Old 08-07-2019, 08:21 PM   #31
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Re: LS bypass fuel pressure regulator question

PERFECT, I can try my experiment now.

Thanks guys!!!
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Old 08-07-2019, 08:35 PM   #32
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Re: LS bypass fuel pressure regulator question

Another quick question....if I have the corvette bypass pressure regulator....does it regulate the pressure down or do I need a regulator downstream of that reg/bypass as well??
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Old 08-07-2019, 08:41 PM   #33
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Re: LS bypass fuel pressure regulator question

It regulates fuel pressure.
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Old 08-07-2019, 09:29 PM   #34
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Re: LS bypass fuel pressure regulator question

Quote:
Originally Posted by weedoublewide View Post
PERFECT, I can try my experiment now.

Thanks guys!!!
Experiment???
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Old 08-07-2019, 10:46 PM   #35
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Re: LS bypass fuel pressure regulator question

^^^pics or it didnt happen ^^
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Old 08-08-2019, 11:34 PM   #36
weedoublewide
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Re: LS bypass fuel pressure regulator question

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Originally Posted by prodjay10 View Post
It regulates fuel pressure.
I missed it on the spec sheet, reg's it down to 58...Thank you sir!!
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Old 08-08-2019, 11:36 PM   #37
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Re: LS bypass fuel pressure regulator question

Quote:
Originally Posted by ls1nova71 View Post
Experiment???
Quote:
Originally Posted by mongocanfly View Post
^^^pics or it didnt happen ^^

I'll be doing my experiment this weekend and ill post some pics of the results for you photo hungry folks!
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Old 08-10-2019, 10:13 PM   #38
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Re: LS bypass fuel pressure regulator question

So I took what nsb29 setup for his fuel return system and adjusted it slightly. As I'm not the best at welding, but decent at soldering.

I was working on the fuel line stuff today and took my pops with me. He's moved from a mechanic job to a sales/specialist job, kudos to not working in the Texas heat now. But he's been mentioning how he doesn't get to use his hands much anymore. So I was like, COME WITH ME..I'll put you to work lol.

So here he is getting the unit out of the truck

Next, we wanted to take nsb29 idea and modified it.

Instead of having two sending units, I condensed it to one sending unit with a return line cut and solder'd it in.
So first was to unsolder one of the pipes from a sending unit and clean it up

Drilled a hole in the new sending unit, and placed it in.

Then finally used some soft solder and a torch and place'd her in her new home
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Old 08-10-2019, 10:15 PM   #39
weedoublewide
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Re: LS bypass fuel pressure regulator question

Still need to clean it up a little with some scotch bright but pretty happy with it.

gotta cut it to length and put the pump and filter on...one beer job lol


QUESTION,

where can I get the fuel pump wires that connect to the pre-existing wires that came with the pump? its the walbro pump I believe
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Old 08-12-2019, 07:01 AM   #40
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Re: LS bypass fuel pressure regulator question

Nice work! I did something similar when i added TBI to a previous truck.

Do you mean a wiring bulkhead where it passes thru the sender top? Gotta be something out there for that. You can just use the sender/hanger for the ground, and only run the power side thru the top. Maybe use the level sensor pass thru out of another sender.
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Old 08-14-2019, 08:27 PM   #41
weedoublewide
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Re: LS bypass fuel pressure regulator question

Quote:
Originally Posted by clay68c10 View Post
Nice work! I did something similar when i added TBI to a previous truck.

Do you mean a wiring bulkhead where it passes thru the sender top? Gotta be something out there for that. You can just use the sender/hanger for the ground, and only run the power side thru the top. Maybe use the level sensor pass thru out of another sender.
Yea I picked a small little do hicky thing up at summit when I was out their this past weekend. I haven't got around to installing it yet, working outside all day long then going to work on the truck in the garage after that doesn't sound very appetizing lol.

OH, I do have a question....should I use PTFE type wire when running it in the gas tank? I read somewhere that the THHN type will, well it won't stand up.

Thank you,

double
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