PTFE or rubber AN lines

[2nd2none]

Pretty new to doing AN lines and need some schooling. I know AN is Army/Navy and the number is how many 16ths of an inch for the hose inside diameter. Until I started looking into them recently I wasn't even aware that theres a PTFE hose in addition to the rubber ones. Was looking at possibly running AN lines for the power steering, fuel, reservoirs to MCs, and at least the lower radiator hose (Coyote in a Mk5). What are the pros/cons of PTFE vs rubber hose? Would you need to run one vs the other in certain applications?

[Mike.Bray]

PTFE is resistant to alcohol like in today's gas. It's usually more expensive than rubber and has a smaller ID. So a -6 hose is more like 5/16" or slightly less.

I don't think you would want PTFE hose on a radiator, too stiff IMO.

[Dgc333]

PTFE (Teflon) is the most chemical resistant material for flexible hose. Most all other automotive hose is CPE (Chlorinated Polyethylene) and is what you will find on your daily driver since E10 and E85 became a thing. CPE will degrade over time but I have never had an issue with it in my 7 to 10 years ownership of my daily drivers.

PTFE is significantly more expensive than CPE, the fittings cost more, the fittings require some specific tools to make up and it takes more skill to make a leak free connection.

FWIW, I am converting my 68 Barracuda to EFI this winter and I am using stainless steel & nylon braid CPE hose with AN fittings for all the fuel lines.

[ProfessorB]

In addition to the already mentioned info, I have found that it is best to NOT mix brands when dealing with AN hose and AN fittings. If you're using Brand X hose.....also use Brand X fittings.

[PNWTim]

+1 on the comment above. For fuel lines, stick with a brand, use PTFE and never look back. High pressure hoses for power steering are a different matter. Perhaps someone else can ring in but I don't think those can be made at home as they may be AN threaded fittings but I believe they are crimped at the hose junction. Radiator hoses can be standard rubber as noted above.

[Mike.Bray]

+1 on the comment above. For fuel lines, stick with a brand, use PTFE and never look back. High pressure hoses for power steering are a different matter. Perhaps someone else can ring in but I don't think those can be made at home as they may be AN threaded fittings but I believe they are crimped at the hose junction. Radiator hoses can be standard rubber as noted above.

I made my PS hoses using PTFE line and AN fittings with no issues.

224589

224590

[Papa]

On my first build, I had no idea what I was doing or what products were better/worse for certain situations. I ordered a fuel system from a vendor that shipped me rubber fuel hose with push-lock fittings. Fast forward a couple of years and my entire fuel system was contaminated with tiny black particles that clogged my fuel pump inlet and killed the pump. I ended up replacing the entire fuel system, but after discussing with others, I used nickel-copper hard lines and carbonized PTFE fuel hose from Aeromotive for the flexible lines. Yes, it's more expensive, but it will outlast the rest of the car. For my new build, I'm using the same approach.

https://thefactoryfiveforum.com/attachment.php?attachmentid=164577&d=1648335194

[phileas_fogg]

Same as Mike; I made my power steering hoses using PTFE line and AN fittings & have had no issues.

Use a pressure tester (https://www.amazon.com/dp/B009S5ICJY?ref_=ppx_hzsearch_conn_dt_b_fed_asin_ti tle_8) and a bucket of soapy water to increase your confidence. I used a bicycle pump to test each line at increasing pressures up to 100psi, and worked the hose side to side at the fitting during each test. No bubbles & no fizzes increased my confidence in my work. I did this for my fuel lines as well.


John

[OB6]

I got all of my power steering hose and fittings here:

https://leepowersteering.com/

They were very helpful and I knew I was getting the right stuff.

[BrewCityCobra]

I made my PS hoses using PTFE line and AN fittings with no issues.

224589

224590

I, too, made my power steering hoses and fuel lines at home - both PTFE.

That that end, the high-pressure PTFE fittings and line that I used for the power steering install was different than the PTFE I used for the gas lines (not sure if that was the same for you Mike or not). I personally recommend Pegasus Auto Racing Supplies for sourcing the power steering materials. A great company with all sorts of info on the positives and negatives of the different types of line/fittings you can use in different situations in a high performance car. They are also helpful if you have any questions.

Pegasus -> https://www.pegasusautoracing.com/document.asp?DocID=TECH00112

[edwardb]

Breeze sells PTFE hose and fittings for power steering lines. I've used them on several builds. Very high quality and highly recommended. https://breezeautomotive.com/shop/hose-06an-braided-stainless-high-pressure-teflon/. For fuel lines and fittings, I use Aeroquip from Summit. Plenty of stories out there about rubber lined fuel hose breaking down and starting to weep over time. Including fuel smell in the garage.

FWIW, on my airplane build completed a year or so ago, the mfg stated that rubber fuel and oil lines had to be replaced after five years. Anything airplane related is conservative for sure. But reinforces that they have a limited life. I replaced with PTFE lines from Pegasus Auto Racing. They were one of the few I could find selling anti-static PTFE lined hose. Which was recommended and I've seen mentioned on here a few times. The hose and fittings were from Goodridge. An English company. Not cheap but probably some of the nicest assembling parts I've used.

Regardless of what you choose, I 100% agree, use hose and fittings from the same company.

[cv2065]

I used PTFE for fuel lines and high pressure PS hoses. Braided Viton FKM rubber for PS low pressure return lines for the flexibility. Deducted brake line rubber hoses for brake/clutch reservoirs, which I think are EDPM rubber. Wilwood and Pegasus are good sources. Don’t use regular fuel hose.

[nuhale]

I used evil energy products from Amazon on both my builds. PTFE for fuel and power steering lines, CPE for radiator lines for coyote (mostly aesthetic reasons). I've used these products in a couple settings and haven't had an issue.

[JMD]

I'll pile on and say I also used PTFE for both fuel and my PS pressure line from pump to rack. Custom made all of them with no problems (although putting on the fittings was a bit of a bear.) I also used the black rubber coated stainless because I wanted to keep the bling to a minimum and it's just another layer to keep the stainless from rubbing the finish off of anything it comes into contact with (because it will). I used Fragola 6000 line and fittings and hope I never have to mess with it ever again! ;)

224695

Just FYI: you don't need high pressure line on the return side of the steering rack. Just between the PS pump and rack. The return is not under much pressure at all as it flows freely and dumps right back into the PS reservoir. I think I used EDPM rubber lines for those as they're much easier to work with and won't degrade in contact with PS or brake fluid like typical rubber lines will. (Also used EDPM rubber lines to brake fluid reservoir.) Here is a pic of those lines coming from rack into PS cooler then back to reservoir.

224696

I wouldn't use AN for radiator hose. Expensive and excessive. I used Breeze stainless hard pipes on the bottom, the FFR supplied accordion pipe on top. Works great and easy to fit, install and remove. But if that's what you really want to do then go for it! You do you. ;)