How small is too small on the return line???
06-18-2007, 10:56 PM
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How small is too small on the return line??? Hi all. Im working up the details for my 77 vette LS1 conversion and had a question. Im using the 99 vette FPR and was wondering how small is too small for the return? I am using 6AN for everything else but would like to use a union reducer right at the tank so I can use my stock 1/4" return line going into the tank. Would that be too much of a restriction with a walbro 255 pump? Also on the FPR, are the inlet and return both 3/8"? Thanks for any help!
06-19-2007, 07:56 AM
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I am actually mounting it in the back about 3 feet from the tank. I plan on running braided line between the FPR and tank. 5/16 to 1/4 isnt bad at all as far as a reduction goes. I was just worried that too small of a return would result in a pressure build up that would defeat the purpose of the regulator.
New question. How do I run a AN fitting on 5/16? They dont make a 5AN do they?
New question. How do I run a AN fitting on 5/16? They dont make a 5AN do they?
06-19-2007, 08:07 AM
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Originally Posted by hosspowerinc
I am actually mounting it in the back about 3 feet from the tank. I plan on running braided line between the FPR and tank. 5/16 to 1/4 isnt bad at all as far as a reduction goes. I was just worried that too small of a return would result in a pressure build up that would defeat the purpose of the regulator.
New question. How do I run a AN fitting on 5/16? They dont make a 5AN do they?
New question. How do I run a AN fitting on 5/16? They dont make a 5AN do they?
06-19-2007, 08:39 AM
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I agree...if you are running 3/8 feed and a 1/4 return...even at 3 feet I would say at idle...its going to build up back pressure. probably at good speed or accel, you wont see any issues...but you MIGHT see a backup of pressure at idle when MOST of the gas is being recirculated. So yes 5/16 would also be my best opinion.
06-19-2007, 08:51 AM
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Actually I will be running -6AN for the 3ft of return and put a reducer right at the tank. Even so, I will change it to 5/16 or 3/8 to be safe. How would I go about doing this I wonder? Could I cut out the existing 1/4" tube, drill the hole larger, and weld in a piece of 5/16 or 3/8? Do they make an o-ring fitting that I just drill a hole and use 2 nuts and a threaded shaft that would run through the tank. One nut on the inside and one on the out? Like a metal valve stem for lack of a better example.
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06-19-2007, 01:28 PM
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Ive been working on it this morning. I ended up using the factory 3/8" feed as a return, removed the factory 1/4" return, and added another 3/8" tube for the new feed. It worked out well since I converted it to a in-tank pump and I have no worries about flow. I just have to weld the new tube in and its ready to go.
06-19-2007, 02:29 PM
#9
That should work out well.. as there have been a few threads on people just doing what you are now or something like it.
I guess you could have gotten away with the 1/4" line, would not have been the best, but it would have worked. But it is better to make the effort now than later..!
I guess you could have gotten away with the 1/4" line, would not have been the best, but it would have worked. But it is better to make the effort now than later..!
