Technical Best Fuel Line Material?

There are also DOT approved compression fittings, a must on air lines on semi trucks when my dad had his business. Kept the tubing from being over swaged.

 

SS, aluminum, and for short hose runs I use the newer hose rated for fuel injection systems. It's tougher, and rated for ethanol based gasoline mixes. A little spendy, but worth it for such short runs as I use it.

 

Not sure those old hoses ever saw any ethanol based gas? I used regular rubber hose in two 6" sections between my fuel cell to my fuel filter to allow me to service the fuel filter on my Austin g***er. Brand new hose started leaking in just 2 years! I walked into my garage to see a 4 ft. puddle of gas under my car! When I removed the hose to replace it I found it was soft and spongy and the gas was seeping through the rubber!
I replaced that hose with alcohol rated high pressure rubber hose a decade ago, and never had another issue.

 

I have Earl's Vapor Guard hoses on most things where flex is required.

Stainless is overkill, but you do you.

Whatever hard lines you use, make sure that they are properly supported and anchored.

Vibration is not good for any of them.

 

Copper. all day long.

 

Nickle copper alloy for brakes is so cheap and so easy to work with I'm surprised anyone uses anything else for much of anything these days.

 

For hard lines I have always used brake line material with inverted flare connections and had no issues. For areas needing hose, just make sure it is compatible with the fuel being used. If they are not compatible, there could be a mul***ude of reactions causing degradation of the hose which leads to leaks.

 

What is the reason for "coiling", what appears to be copper line? Is it to give it an area of flex, to keep it from cracking?

 

Here in California, ethanol laced fuels are all there is. Now I may have gone overkill on Ol' Furd, but I went SS hardlines back to front with PTFE braided hose and AN fittings for the flex lines. To me, it's only a little more difficult to work with than plain steel. There is no way I'd use aluminum for fuel lines. My OT drag racer, which runs on methanol, would have eroded aluminum fittings after two seasons. At the beginning of one particular season, I had fuel leaks pop up one right after another. Fix one, another let go.
I didn't wanna get stuck in BFE somewhere with Ol ' Furd with failed fuel lines. So I went the extra mile.
I did use a rubber hose for the vent line. Two years after the truck was up and running, and happened to check it while I was in the neighborhood, so to speak. It was hard as a rock. Goodyear brand emissions hose.
Either the fuel vapors are responsible, or rubber hose just ain't what it used to be.....or both.
YMMV

 

Kelly,
Yes, that's right.

 

@Mike Lawless Do you have any pictures of your lines?

@Ericnova72 thank you!

 

Here's a motor shot. You can see the hard lines on top routed around the valve cover, with the PTFE braided lines connecting those to the ch***is lines. The ch***is lines run along the side of the frame rail all the way to the tank, and connect to that with a short PTFE braided line.
What remains to be seen is how long this will stay up before being taken off, since the induction is OT. It is here for illustration purposes only and to respond to Kelly Burns request.

 

@Mike Lawless thank you, I saved it, in anticipation of the removal! LOL