Thoughts on fuel line run options (PTFE/Nickel copper)

[Fman]

I am starting to think about fuel lines, my engine will have EFI so I need a return line as well. I originally was planning on running 3/8 Nickel Copper under the frame then into 3/8 PTFE braided. I just ordered my 255 LPH fuel pump/regulator from a reputable builder and I was recommended by him to just run the 3/8 PTFE line from the pump to the regulator in one line under the car and eliminate more fittings. I would also need another line for the return line from the regulator (mounted on firewall) which would also be PTFE line. So I would have two PTFE lines running along the frame rail. He told me these PTFE lines are used on helicopters and are very durable.

Is there a problem running PTFE lines under the car? or is this a QB option and both work equally well? I like the idea of less connections to eliminate potential leaks, but definitely do not want to run a line that is not durable with good longevity.

[AC Bill]

My understanding is the PTFE is better then the steel braided rubber lines, but I also believe personally, the solid galvanized steel lines are the most durable over time. They have a pretty good track record. Chances are, your car will never be put through the abusive road conditions that many vehicles are, ice, snow, mud, gravel, salt, etc., under which the steel lines have endured for 30 years plus, before needing replacement.
You can get a roll of stainless, aluminum, or galvanized in a roll, and run one continuous length, to avoid more fittings. Bending one single length piece could prove challenging, but I understand builders have done it. The compression fittings, tightened properly, shouldn't be an issue leak wise, if you find it easier to use a couple of sections. You can also avoid having to flare your lines for the fittings, by buying pre-made lengths of it. Brake lines use the same fittings, and they withstand far higher pressures then a fuel line.

In my case, I used armored galvanized steel lines, for both brake and fuel.

[NAZ]

I ran -8 PTFE SS braided hose the entire length of my fuel system on the race car -- supply, return, and connector lines. More expensive, take up more room, and slightly more weight but IMO, much safer in a crash than hard lines.

[CDXXVII]

I ran stainless steel hard lines and used ptfe stainless braided for final connections

https://thefactoryfiveforum.com/attachment.php?attachmentid=82790

https://thefactoryfiveforum.com/attachment.php?attachmentid=82791

https://thefactoryfiveforum.com/attachment.php?attachmentid=82792

https://thefactoryfiveforum.com/attachment.php?attachmentid=82794

[sread]

You sir, are an artist. I just finished running the nicopp fuel lines in my car and it was quite the challenge to make it look clean and zig-zag as necessary to go from A to B . I can't imagine doing it in stainless. That looks awesome! How do you get such precise uniform bends?...and how many tries does it take?

[NAZ]

Beautiful work, it's apparent you are a craftsman and take pride in your work.

[Fman]

I ran -8 PTFE SS braided hose the entire length of my fuel system on the race car -- supply, return, and connector lines. More expensive, take up more room, and slightly more weight but IMO, much safer in a crash than hard lines.

Do you have any pics of your install? What is the hose size with -8 AN fittings? I believe he mentioned he wanted me to run -6 AN fittings. I was told all I would need is equivalent to 3/8" line.

[NAZ]

Do you have any pics of your install? What is the hose size with -8 AN fittings? I believe he mentioned he wanted me to run -6 AN fittings. I was told all I would need is equivalent to 3/8" line.

Sorry, no photos of my fuel line run through the chassis. Most folks here will be fine with -6AN fuel lines, my little 406 makes 1,100 HP so I need -8AN fuel line to supply enough fuel at low pressure to the carb. AN sizes are in 1/16" increments so -6AN hose is 3/8" nominal I.D. and -8AN is 1/2" nominal I.D. Remember, tubing size is measured on the O.D. and pipe & hose on the I.D. The fitting thread size for -6AN is 9/16-18 and -8AN 3/4-16 so a large difference.

[D Stand]

That stainless line install looks great! I was going down that path but a buddy was building a Nova and ran all PTFE line and it was a clean install. You need to have the right fittings for the type line you are using. If you go this route, go to hotrodfuelhose.com as they have a good overview of its use and have all of the fittings available. There are supporting vendors here that sell the product but these guys have good resources for educating yourself on whether you should go this route.

As for the -6 line versus -8 line. The math is times that number by 1/16” to get your inside diameter “. When you use stainless, or any other tubing the numbers are for outside diameters. I bought my kit used and the previous owner bought all stainless lines to replace the factory stuff. I am running fuel injection and needed 3/8” line. The 3/8” stainless line I had was only 3/16” inside.... this is why a scrapped it and went with the PTFE. I ran my in the same path as CDXXVII

[rich grsc]

16 AN=1", 8 AN=1/2" 6 AN=3/8". See the relationship? :D

[TMartinLVNV]

I ran stainless steel hard lines and used ptfe stainless braided for final connections

That is beautiful work. I want to be like you when I grow up :p I don't have near the skill to pull something like that off.

I cheated with my brake lines. I used braided stainless brake lines for my entire run. I had a friend who owns a hydraulic hose shop build these for me.

https://i413.photobucket.com/albums/pp213/tmartinlvnv/DSC03479.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/DSC03479.jpg.html)

https://i413.photobucket.com/albums/pp213/tmartinlvnv/DSC03495.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/DSC03495.jpg.html)

For my fuel lines, I did the entire run from the pump to the Holley sniper hookup with -6 AN stainless braided PTFE fuel lines. Super easy to run, but they are a bit bulky. At the back of the car, I ran an extra loop in both lines so that I can drop my fuel tank without having to disconnect them from the hanger. I don't know if this will ever by useful, but I thought it was a good idea at the time. I got pretty good at attaching the AN fittings on the braided lines at the end. Cutting the lines with battery cable cutters led to much less fraying of the braiding than taping and cutting with a saw.

Love the cat in your picture. Dog owners don't know how much help a cat is during one of these builds. Even though they don't have thumbs, cats are great and pointing out (by sniffing) areas that need extra attention ;) They are great for helping you relax after a long day in the garage.

https://i413.photobucket.com/albums/pp213/tmartinlvnv/IMG_20200628_141517675.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/IMG_20200628_141517675.jpg.html)

[Fman]

That is beautiful work. I want to be like you when I grow up :p I don't have near the skill to pull something like that off.

I cheated with my brake lines. I used braided stainless brake lines for my entire run. I had a friend who owns a hydraulic hose shop build these for me.

https://i413.photobucket.com/albums/pp213/tmartinlvnv/DSC03479.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/DSC03479.jpg.html)

https://i413.photobucket.com/albums/pp213/tmartinlvnv/DSC03495.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/DSC03495.jpg.html)

For my fuel lines, I did the entire run from the pump to the Holley sniper hookup with -6 AN stainless braided PTFE fuel lines. Super easy to run, but they are a bit bulky. At the back of the car, I ran an extra loop in both lines so that I can drop my fuel tank without having to disconnect them from the hanger. I don't know if this will ever by useful, but I thought it was a good idea at the time. I got pretty good at attaching the AN fittings on the braided lines at the end. Cutting the lines with battery cable cutters led to much less fraying of the braiding than taping and cutting with a saw.

Love the cat in your picture. Dog owners don't know how much help a cat is during one of these builds. Even though they don't have thumbs, cats are great and pointing out (by sniffing) areas that need extra attention ;) They are great for helping you relax after a long day in the garage.

https://i413.photobucket.com/albums/pp213/tmartinlvnv/IMG_20200628_141517675.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/IMG_20200628_141517675.jpg.html)

Terry, I am with you bending Nickel Copper was challenging for me, can't even imagine doing stainless. Do you have any pics of your PTFE fuel lines mounted up? Is it on your build thread? I can always reference that if there are pics there. I have talked to a few other guys who have ran PTFE steel braided entire run and seem to be happy with it, definitely simple and I like having minimal amount of fittings to leak.

Thanks...
Travis

[TMartinLVNV]

Travis, I'll take some tonight as best as I can. Honestly, when I installed them, it was so easy I didn't bother to take pics.

I'll photo as much as I can with the car on the ground. It will give me a reason to take the cover off while I sit in limbo before my DMV appointment. One more week to go !

[cv2065]

Took me a few tries to get the right bottle sizes to bend the NICOPP, but it was pretty easy to bend. Cheap pipe bender was needed as well. Hardest part was not crushing the tube on hard 90 degree bends..takes some finesse for sure. I used pre-made lengths from the local jobber, which made it a little more challenging when planning out the routing, but was easier if I jacked something up. And I agree, CDXXVII's work is very nice!

[JohnK]

The nice thing about Nicopp is that it's relatively inexpensive for a roll of it (as compared to stainless steel). I actually bought a roll of Nicopp to practice with before attempting to make my brake and fuel likes out of SS. I'm glad I did. I've learned a ton about bending accurately through all my screw ups with the Nicopp lines.

[AC Bill]

CDXXVII , you did an awesome job of running those stainless lines. Damn near surgical..

It's such a shame that they really can't be seen better by onlookers.

[TMartinLVNV]

This is the only part that I can photograph. It is damn near impossible to get anymore with the car on the ground. You can see the send line going into where the pressure gauge is and the return line on the passenger side of the throttle body. I bought the black AN fittings but many colors are available. Use an AN fitting wrench (aluminum) or you will scratch them easily.

https://i413.photobucket.com/albums/pp213/tmartinlvnv/DSC03860.jpg (https://s413.photobucket.com/user/tmartinlvnv/media/DSC03860.jpg.html)

I originally purchased the fuel injection kit from F5 when ordering the car. I was underwhelmed with what was delivered and it was less capable than what was required from Holley. So, I replaced darn near everything.

I purchased the Pro-M 3/8" hanger which -6 AN fittings screw right onto. My fuel filter and charcoal canister are mounted just in front of the fuel tank on a horizontal frame bar. I coiled both lines before these connections in the void above the solid axle and in front of the fuel tank so that I can drop the tank without disconnecting anything if needed. The F5 lines run in the trans tunnel as they were not long enough to run along the right side frame. I ran my replacement braided -6 AN lines the same route through the tunnel. Several people say not to do this as the lines might be damaged if there is a catastrophic failure in the trans tunnel. I'm not worried about it with the stainless braided lines and the apparent lack of catastrophic failures throwing parts around in the trans tunnel on our cars driven on the street. If I was doing it again from scratch, I would probably run them along the right side of the frame because it does look cleaner. I used a series of two "P" clamps in the rear of the car and in the trans tunnel to mount and space the lines. One 3/16" rivet through both holes in the "P" clamps secure things nicely. In the engine bay, I used the aluminum spacers to route the lines parallel together and look pretty. Remember to allow enough slack in your lines in the engine bay to account for the engine moving on the mounts. I had the F5 regulator mounted on the back wall of the engine bay but removed it because the Sniper does this on its own.

[Fman]

Travis, I'll take some tonight as best as I can. Honestly, when I installed them, it was so easy I didn't bother to take pics.

I'll photo as much as I can with the car on the ground. It will give me a reason to take the cover off while I sit in limbo before my DMV appointment. One more week to go !

Terry, I am stoked for you, your so close to having your car titled... you should be proud of that car you did a damn fine job on it!

Appreciate any pics... I actually kind of like the look of the PTFE braided lines, more concerned about a clean install, functionality and safety. I will be fine with running braided lines tucked up under the car that nobody will ever see once the body is on.

[NAZ]

Fman, if you decide to run PTFE lined SS braided hose for fuel line; there are some significant differences between PTFE and standard AN “rubber” braided hose and hose ends you need to be aware of.

You can mix and match manufacturers’ AN hose and hose ends made to a military spec and I’ve had no issue interchanging hose and hose ends from the more popular commercial manufacturers. However, I’ve seen PTFE hose dimensions vary from manufacturer to manufacturer enough that the hose ends are not interchangeable. So, stay with one brand for all your PTFE hose and hose end needs to ensure compatibility. You will also find that PTFE hose ends are limited in type and style compared to standard AN hose ends; which sometimes becomes a challenge to run PTFE lines because of this and some manufacturers are more limited than others.

Another important note about PTFE hose, you want to use the anti-static hose. The anti-static version is made with graphite. The issue is static builds as a fluid flows through the non-conductive PTFE hose until it arcs to the S.S. shield. This causes damage to the hose which can develop into a leak. I prefer the Fragola Performance Systems 6000 Series PTFE hose and hose ends. The 6000 Series uses a black conductive liner from -6 to -12 sizes and they have a good assortment of hose end styles. Some manufacturers exclusively use the white non-conductive liners which may become problematic.

But no matter what you use for fuel line, I suggest you carefully consider how you route your lines. Some folks run their fuel and brake lines near the driveshaft which is a profoundly bad idea. I’ve had two driveshaft explosions and submit to all reading this; the damage is impressive. Both were on street vehicles operating on the street so that lame excuse that it only happens to race cars is simply BS.

[Fman]

Fman, if you decide to run PTFE lined SS braided hose for fuel line; there are some significant differences between PTFE and standard AN “rubber” braided hose and hose ends you need to be aware of.

You can mix and match manufacturers’ AN hose and hose ends made to a military spec and I’ve had no issue interchanging hose and hose ends from the more popular commercial manufacturers. However, I’ve seen PTFE hose dimensions vary from manufacturer to manufacturer enough that the hose ends are not interchangeable. So, stay with one brand for all your PTFE hose and hose end needs to ensure compatibility. You will also find that PTFE hose ends are limited in type and style compared to standard AN hose ends; which sometimes becomes a challenge to run PTFE lines because of this and some manufacturers are more limited than others.

Another important note about PTFE hose, you want to use the anti-static hose. The anti-static version is made with graphite. The issue is static builds as a fluid flows through the non-conductive PTFE hose until it arcs to the S.S. shield. This causes damage to the hose which can develop into a leak. I prefer the Fragola Performance Systems 6000 Series PTFE hose and hose ends. The 6000 Series uses a black conductive liner from -6 to -12 sizes and they have a good assortment of hose end styles. Some manufacturers exclusively use the white non-conductive liners which may become problematic.

But no matter what you use for fuel line, I suggest you carefully consider how you route your lines. Some folks run their fuel and brake lines near the driveshaft which is a profoundly bad idea. I’ve had two driveshaft explosions and submit to all reading this; the damage is impressive. Both were on street vehicles operating on the street so that lame excuse that it only happens to race cars is simply BS.

Thanks for this info, all my lines/pump/fitler/regulator are coming from Mike Forte. He has been at this for awhile so I can only assume he knows what he is doing. He mentioned the lines are used in Helicopters and would be totally fine for my car. Once I get the fuel line lengths he will make them at his shop and send them out to me with the fittings attached. I was planning on running the lines on the passenger side outside the frame, similar to how I routed my brake lines.

[Hacksaw84]

[QUOTE=CDXXVII;418176]I ran stainless steel hard lines and used ptfe stainless braided for final connections

Those look amazing!! Please come over to my house.