Braided Lines from Tank Forward S14

[Jorge1190]

I am re-doing my fuel system this winter and was considering running -6 line all the way from the tank. I was wondering if anyone here had done this before considering the S14 tank is plastic.

I know they make bulkhead fittings that can work, however I don't know how well they would work in this since it is a saddle tank with not much flat surface.

[Def]

Why not go through the pump plate?

[Jorge1190]

I'll look into that, it is also plastic but might work for bulkheads. I am hoping someone has done it and can post a picture.

[Z28ricer]

Why spend a whole bunch of money on fuel line that really isn't going to gain you anything ?

Maybe just buy stainless or aluminum tube and bend up some new hardlines if you really need a diameter increase ?

[josh_s13]

The summit racing steel braided fuel lines are almost as cheap as buying and bending tube. It's pretty high quality, the lines that I had survived a fire.

As far as the bulkhead fittings go, they should be fine to go into the stock tank. If you have to use a sealant I would recommend staying away from the local auto parts store. 3M and DOW make some great sealants designed for aircraft use that can handle ethanol and any other crap that goes into your gas tank without self destructing. I think that the 3M products are a bit cheaper than DOW. Both company's should have product support engineers that can guide you in the right direction.

That said, as Z28ricer mentioned before, you will end up spending $150 +on something that probable won't buy you the slightest performance advantage over what Nissan installed. If it were me, and I intended to run fuel injection, I would search for a used line in good condition.

I think that my hard lines are still bolted to the bottom of my car, if you just need replacements I may be able to give you mine.

[Jorge1190]

There is nothing wrong with my hardlines it was more of just something I was thinking about doing as I plan to run base pressure at 60 PSI in the near future.

After some more searching I found rubber line that is rated to high PSI to replace the lines from the tank to the hardlines. The small rubber ones. The lines from the firewall forward will be done in braided line.

[josh_s13]

I have functional tested the OEM lines at 90PSI, and have run them at 55PSI without issue. That was on new rubber lines with the original Nissan hardline.
If you only do firewall forward braided it should only cost a few dollars. The only issue I could foresee would be adapting the stainless line to the solid factory line since stainless braided line seems to need more than a worm gear hose clamp. Aeroquip makes a high pressure, high temp polyester braided line that is clampable IIRC.

[jfryjfry]

Run steel lines and flare the ends, using adapters to get you to the braided lines at the end. Cheapest and most reliable.

[Matt93SE]

I know maxima guys that have run over 100psi on the stock steel lines. Those steel lines are stronger than anything short of a braided stainless line, especially ALU or copper like many people seem to think they should run.

[CodyAce]

Not to mention that you need to run a 'fuel safe' line for the modern ethanol fuels.

[Jorge1190]

Yeah after thinking about it some more I am going to replace the short rubber lines from the tank to the hardlines with some high pressure rubber line. The AN lines up front will be flared and attached to the hard lines with tube nuts and adapters.

[Beejis60]

I know maxima guys that have run over 100psi on the stock steel lines. Those steel lines are stronger than anything short of a braided stainless line, especially ALU or copper like many people seem to think they should run.

Someone on here was saying they used aluminum fuel lines with no problems, but I think he said flaring was a bitch or something. I'd be more worried about denting and subsequent kinking/breakage.

Yeah after thinking about it some more I am going to replace the short rubber lines from the tank to the hardlines with some high pressure rubber line. The AN lines up front will be flared and attached to the hard lines with tube nuts and adapters.

Ya, definitely don't use those compression fitting/adapters... I hear they can't hold pressure worth a damn.

[Def]

Aluminum flares pretty easily, but you can crack it on the flare with a cheap flaring tool. Using oil on the flaring mandrel helps a lot.

Even an 0.028" wall thickness aluminum line will hold 150 psi, and the usual 0.063" people run is going to hold WAY more fuel pressure than you will ever get out of a fuel pump.

Stock steel lines can probably hold 500 psi without issue.

It's not hard to calculate the hoop stress and see what percentage of yield it is at a given pressure.

I would not run all braided lines, as they are permeable to fuels to various degrees.

[Beejis60]

I would not run all braided lines, as they are permeable to fuels to various degrees.

The teflon-lined ones I thought are supposed to be kosher to all fuels? They're just balls expensive for them and their respective fittings.

Either way, I was stupid and made braided lines long ago and one day, I would like to redo in stainless or aluminum...

[Jorge1190]

With Ethanol you do need to be careful about which lines you use but I run on pump gas so most steel braided line will work.

With Ethanol I would also be running a lot larger than -6. Thanks for the responses everyone.