Fuel System Question
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I got my twin Walbros installed, hooked up the lines & wiring the way I thought they should be. Put the tank into the car & started removing the old lines to run the braided ones. And then the 3rd line question hit me. What am I supposed to do with it? There isn't anything in the instructions covering this, searching found nothing and I guess I'm dumb.
Since I am using a Vic Jr intake on this setup, I don't have anywhere to connect it to on the engine. Do I just leave the line hanging off the tank? And did I connect the braided lines to the correct 2 of 3 lines on the tank? (see pic) I figure I got the pump line right, but I'm questioning the return line connection now.
This is the Nasty Stage 3 system with a hobbs switch for pump #2 & a boost ref'd regulator between the fuel rails & the tank. I posted in the fuel forum, but thought maybe someone here might know....
Thanks
Mark
Since I am using a Vic Jr intake on this setup, I don't have anywhere to connect it to on the engine. Do I just leave the line hanging off the tank? And did I connect the braided lines to the correct 2 of 3 lines on the tank? (see pic) I figure I got the pump line right, but I'm questioning the return line connection now.
This is the Nasty Stage 3 system with a hobbs switch for pump #2 & a boost ref'd regulator between the fuel rails & the tank. I posted in the fuel forum, but thought maybe someone here might know....
Thanks
Mark
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I don't know the specifics of the dual intank Walbro setup, but i'm just taking some guesses here at the setup.
Are the 2 braided lines you have there both pressure lines? #10? If so its overkill. A single #10 will supply all the fuel you need. If needed you can put a YBlock in to the single #10. You can use a #8 or #10 return. Also running 2 pressure lines is alot of extra weight.![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
Are you planning on running a return line?
I know most of the OEM LS1 cars use a fuel system without a return, but I think when you start adding more pump to it, a return would be for the best. That may be your third line..... The return doesn't need any valves, baffles etc, as it is going to just dump back into the tank. The only other item really necessary is the vent.
Good luck!
Are the 2 braided lines you have there both pressure lines? #10? If so its overkill. A single #10 will supply all the fuel you need. If needed you can put a YBlock in to the single #10. You can use a #8 or #10 return. Also running 2 pressure lines is alot of extra weight.
![Winky](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_wink.gif)
Are you planning on running a return line?
I know most of the OEM LS1 cars use a fuel system without a return, but I think when you start adding more pump to it, a return would be for the best. That may be your third line..... The return doesn't need any valves, baffles etc, as it is going to just dump back into the tank. The only other item really necessary is the vent.
Good luck!
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Thanks Kurtis. I think the 3rd line is just an Evap return line, so it shouldn't matter much, but I thought I'd ask before I put the 9" back in just in case. And I have an 8 AN from the pump with a 6 AN return from the regulator....supposed to be enough for 1000hp.
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I have three lines on mine. Two, one from each pump to the back of my rails, then a crossover at the front rails into a regulator which has a third line that is the return to the tank. Is yours the same, not sure, cause the dual intank pump kits I have seen (Lonnies for the vettes) have the two pumps tee'ed together in the tank and just one outlet. Mine is full custom one off, and 2nd pump is on an rpm activation sw.
Robert
Robert
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The line that connects to the intake is a vent for the tank. I talked to the guys at nasty about removing it and thay said that it would leave the tank to vent into the atmosphere and would leave vapor in the air. I have talked to a few on this board that have said that thay havent smelled anything. On some newer cars the tank vents in to the fill tube, not sure if that would help or not. So if you eliminate that line you should have a fuel supply and a return. Not sure if this help in your situation or not.
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There is a feed and return line the 3rd small line goes to the charcoal canister and gets left in place it goes no where near the T fitting on the fuel filter it is a separate line that goes back up front to your intake. It is your tank vent and routes all the vapors to the intake. it MUST be left in tact.
Nate
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There is a feed and return line the 3rd small line goes to the charcoal canister and gets left in place it goes no where near the T fitting on the fuel filter it is a separate line that goes back up front to your intake. It is your tank vent and routes all the vapors to the intake. it MUST be left in tact
Nate
Nate
A few months late but great info
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