Stainless steel hard brake and fuel lines vs standard steel hard linesl

[grannyknot]

There is also this stuff, not SS but it looks the part,

https://www.toolsource.com/tubing-benders-c-1321_79_90_261/ezibend-tube-316-in-od-25-ft-p-106469.html?tsqtid=&zenid=vsahb758cdn811ipdhtta9g1s6

[ksechler]

I used the classic tube ss brake lines.  They fit very well.  I had to convince the front passenger one a little but nothing serious.  Stainless is harder to bend.  As far as cracking - I've never heard that one.  A quick (and lazy) trip to google produced this quote, "...so that as a general rule ferritic and martensitic types cannot be expected to be as fatigue resistant as the austenitic stainless steels..."  meaning carbon steel lines are more likely to fatigue and crack than stainless.

[madkaw]

Being pre-bent , I would go SS.

 

Bending SS line is a bitch especially when you start getting to bigger lines like 5/16” or bigger . You can’t just reach up under there and tweak the bend with your hands - unless you are incredibly strong .

i just did 3/8” SS for supply line in the stock position and it was really tough especially when you have to pull it out every time you need to tweak it

[JeffMopar]

OK, here is a pic. You can see the difference with the fuel line which is normal steel. Everything else is stainless.

[Captain Obvious]

8 hours ago, ksechler said:

as a general rule ferritic and martensitic types cannot be expected to be as fatigue resistant as the austenitic stainless steels..."  meaning carbon steel lines are more likely to fatigue and crack than stainless.

I don't think that's what they're saying with that quote... All three of those categories are stainless. In other words, ferritic, martensitic, and austenitic are all varieties of stainless.

So what I get out of that quote is: "As a general rule, ferritic and martensitic varieties of stainless are not as fatigue resistant as austenitic stainless."

I'm no materials guy, but I don't think you can glean "carbon steel is more likely to fatigue than stainless" from that quote.

 

[jensend]

14 hours ago, cbuczesk said:

I know that SS lines have been used in the muscle car world for over 10 years and I've never heard of an issue. I can tell you that getting the brake lines to completely seal at the connection take a lot of torque. Other than that I have no complaints. I used SS brake and fuel lines from The Right Stuff on my Road Runner and AAR. I think my brother has them on his '67 Belvedere II.

Chuck

 

That's what I was thinking.  Many manufacturers have been using stainless steel for a while now.  To me, it's the possible problem of getting a good seal at each of the flares.

Thanks for your input.

[jensend]

10 hours ago, ksechler said:

I used the classic tube ss brake lines.  They fit very well.  I had to convince the front passenger one a little but nothing serious.  Stainless is harder to bend.  As far as cracking - I've never heard that one.  A quick (and lazy) trip to google produced this quote, "...so that as a general rule ferritic and martensitic types cannot be expected to be as fatigue resistant as the austenitic stainless steels..."  meaning carbon steel lines are more likely to fatigue and crack than stainless.

Great, thanks.  Did you have any trouble sealing the flares at each connection?  My understanding is that you don't necessarily have to crank them super hard, you just have to tighten, then back them off, then tighten back down.  Do that a few times to seat the fittings and its good.  Is that your experience?

Also, are the classic tube ss lines metric threads and wrench size, as in 10mm?

Thanks for your input.

Edited December 12, 2017 by jensend

[jensend]

9 hours ago, madkaw said:

Being pre-bent , I would go SS.

 

Bending SS line is a bitch especially when you start getting to bigger lines like 5/16” or bigger . You can’t just reach up under there and tweak the bend with your hands - unless you are incredibly strong .

i just did 3/8” SS for supply line in the stock position and it was really tough especially when you have to pull it out every time you need to tweak it

I'm going pre-bent.  I'm just trying to decide whether to go SS or OEM.  

[jensend]

1 hour ago, JeffMopar said:

OK, here is a pic. You can see the difference with the fuel line which is normal steel. Everything else is stainless.

Ok, great.  Thanks for your input, Jeff. 

[cbuczesk]

7 hours ago, jensend said:

Great, thanks.  Did you have any trouble sealing the flares at each connection?  My understanding is that you don't necessarily have to crank them super hard, you just have to tighten, then back them off, then tighten back down.  Do that a few times to seat the fittings and its good.  Is that your experience?

Also, are the classic tube ss lines metric threads and wrench size, as in 10mm?

Thanks for your input.

Yes. The trouble is sealing the flares at each connection. I've done the tighten/loosen game and have to keep going tighter each time until it seals. I then press the brake pedal really hard and checks for leaks. I haven't pulled any threads from over-tightening and they've always sealed so I'm happy with them.

Chuck

 

[ksechler]

10 hours ago, jensend said:

Great, thanks.  Did you have any trouble sealing the flares at each connection?  My understanding is that you don't necessarily have to crank them super hard, you just have to tighten, then back them off, then tighten back down.  Do that a few times to seat the fittings and its good.  Is that your experience?

Also, are the classic tube ss lines metric threads and wrench size, as in 10mm?

Thanks for your input.

I had one or two flares that I had to crank down on to seal but overall they were great.  Frankly, it never occurred to me to loosen and retighten but that sounds like a better approach than risking stripped threads.

The classic tube is whatever the OEM threads are (assume metric).  The wrench is a 10mm.  Get the proper flare nut wrench.  You'll thank yourself later.

[jensend]

So, a little feedback from my experience with redoing all the hard lines in my '73 Z, except for the fuel vent line.  I went with Classic Tube's stainless steel version of their pre bent lines rather than OEM steel. I had them send me an enlarged fuel return line (5/16th) rather than the stock size.   I took a fine scotch Brite pad to them to shine them up and the end result to me looks awesome.  They are just the look I was going for against the blue paint, which I had just repainted in the engine bay.  For each connection, I tightened and loosened about 6 times each as recommended by Classic Tube, and each connection sealed nicely.  Also, threads are 10mm, but the flare nut is a 7/16".  I bought, just for the occasion, a nice Snap On flare nut wrench to do the job so I didn't round any corners during all the tightening and loosening.  The connections worked well.  They come with nice, solid flare nuts to work with.

However!  I found that the lines as shipped ONLY VAGUELY resembled my original lines and in no possible way would any of them (not even one of the shortest lines) just drop into the little retainers along their paths.  All of them needed major manipulation in the form of unbending and rebending to get them to sit nicely in their respective grooves.  It took several days of work and very sore hands to make them work out.  And in some areas deep in the back of the chassis I barely got them to fit.  If I didn't just happen to be an orthodontist where I bend wire for a living, they never would have worked and I would have been completely frustrated.  Stainless steel is definitely harder, but not unbendable.  My biggest complaint is that I halfway was expecting the lines to just drop right in. The other half of me was thinking that must be too good to be true.  In my experience,  a perfect fit as shipped was too good to be true. 

But I was able to make it work, and the end result, I think, is beautiful.    

Edited March 26, 2018 by jensend