What's the difference between the racing SS brake hoses and the street ones?
My car has the racing ones on right now, but I do have the street versions on standby.
The street set has gone through the D.O.T. ,testing, paperwork process of approval. The "race" set has not. They could be the same or who knows.
Steve
Though you get a firmer pedal, keep an eye on the stainless brake hoses, they do goet old and break (the inner lining). It can make for an interesting experience (ask me how I know!).
I'd stay with the DOT ones, or stay with the original rubber lines. If you do keep the stainless hoses, do keep an eye on them. Remember, these are routinely checked on a race car, not so on most street cars!
This is a question for Chris or Ed at Tangerine Racing.
Steve is correct. the Teflon lined ones do not degrade without mechanical confrontation. some racing lines may have the universal backing clips while DOT would be 914 style. some "race " lines may be of inferior quality since they are not required to pass certification caveat emptor
Whichever of the 2 you choose, it's wise to replace them every 2 years, if not sooner. Remember, the failure mode is gradual clogging on the rubber hoses, about 15-20 years out. The failure mode of SS braided teflon lines in catastrophic and random, often happening within a few years, the result is NO BRAKES, and it is instantaneous. The Cap'n
The DOT is concerned with "now", not the longevity of the product as installed. Any automotive service professional familiar with this product will tell you to regularly inspect the hoses for abrasion and corrosion, and that they need to be replaced often. They were originally intended for race cars, not for use in the street, and race cars are driven on clean tracks, for the most part, and only a few hours a year. Besides all that, they offer little or no performance improvement over what came on your car from the factory. If they did, don't you think the makers of high cost, high performance cars would install them at the factory? They're "bling" for everyday use, and dangerous "bling" to boot. This has been discussed before, at length, and I've offered far more expansive answers in the past. A search might bring those up. How many conventional brake hose catastrophic failures have you seen? As a professional wrench, I've personally seen close to a half dozen SS covered teflon hose failures, out of what I calculate to be the cars of less than a small fraction of 1% of my customers' cars.
The Cap'n
I had a SS hose blow out once . Never has a stock hose blow out on any street car/truck in 100k's miles of use.
You decide....
Very good info in this thread. I have DOT approved stainless steel going on and now know to watch them periodically as you should for all brake items. Next time I will go with the rubber type since they appear to be the best and probably can watch the external deteration, etc easier.
Great info.
Steve Hurt
I worked in the aircraft industry for years and I never saw a teflon lined SS hose fail. That is all the aircraft manufactures use. I've seen fittings leak or the line abraded but I've never seen one pop. A failure would be catostrophic. Aircraft have redundant hydraulic pumps but not reservoirs. I'm sure FAA testing is more stringent than the DOT.
That being said I've never seen a SS hose used in an application that subjected it to that much movement. Aircraft use them in locations where vibrations would cause a solid line to work harden. Their range of motion is very limited. Your asking alot of that teflon everytime you go from lock to lock. Take a piece of that teflon and bend it with your fingers. You'll see it kink and it'll turn white at the bend. Anytime that line flexes after that it will work harden the kink and eventually fail.
I like the idea of not losing volume/pressure due to line bulge but it's really the wrong application for the product.
I don't get it. If that hose is as deadly as you and the Cap'n say it is how could it meet the DOT product standards and pass the tests? Those standards are new and current, published in 2005, I believe. Is DOT totally unaware of the problem? Why don't the new standards identify those problems? Is it that DOT just doesn't care? Have any of these failures been reported? Are the manufacturers (there are a lot of them) aware of the problem?
Hot coffee provoked a lawsuit, so you'd think unpredictable and catastrophic brake faliure would provoke at least one or two. No? Then why not? I really don't get it.
I don't think that many racers were too concerned about where to report any failures, but I will testify that when they do fail, it's pretty exciting.
The opinion that they are "bling" is probably correct. I would not replace a rubber hose with a stainless one anymore. It seems that a lot of the pedal "firmness" that we were all looking for was lack of properly bled brakes and bending floorboards more so than expanding brake lines.
Fair enough and I have no doubt about that, but these are used on street cars as well. These are DOT approved hoses, not the unapproved racer type. Surely those failures showed up in police accident reports somewhere.
These questions aren't because I'll ever be using braided stainless lines again, I'm convinced. I'm just curious about what DOT's role is, since they have a relatively new performance standard specifically for these products. Seems they've been a bit like FEMA. Or the banking regulators.
The SS hose is a great product. There's only one problem. Once it reaches its elastic limit it's junk. It's a failure waiting to happen. The major problem being that it fails all at once. When rubber lines go bad they give you a heads up. A spongy pedal and increased stopping distance makes you stick your head under the car.
DOT testing is done in a controlled environment. If they don't subject the hose to its elastic limit it's all good. It passes with flying colors. The last time I hit the streets about the only thing I controlled was the radio station. It's far from perfect.
On a track car I'd run them. Every little bit helps. Limited hours, smooth courses and frequent inspections limit the possibility of failure. Not to mention the environment is somewhat controlled. I've never seen a little kid run across the track to get a ball.
For sake of discussion, say you do have a failure and an accident. If they are DOT your insurance company won't have anything to say. But if they are not your claim could be denied.
That should be true since they will look at ways to deny you.
Though if you kill someone because of a component failure the majority said not to use you would feel pretty badly (that was not meant to be a shot at you Paul).
Again for sake of discussion, is there any way to tell DOT braided from non-DOT except for the clips?
with the cap'n, I too have seen the failures, I too won't have them on my cars (DOT or not) and I too have have discussed this to death here.
BTW I have used them on my full flow oil system but like jmill said they only see vibration. But lately I only seem to use Parker push-lok hoses for FF.
I don't know the protocol for how the DOT process is controlled, but I suspect it has something to do with testing, equipment calibration, and documentation. Any non DOT braided brake line I ever purchased was tested to the same standard, though it was probably not documented, and the test equipment may or may not have been within its calibration cycle. There may be more, but I suspect it's a rather loosely controlled requirement, since there are so many aftermarket companies and brake hoses available. Costs would also reflect the level of compliance required, but hoses are generally a pretty cheap component and not likely held to extraneous requirements; me thinks.
Andy1
I apologize for beating this to death, but here we go.
I’m honestly intrigued that the agency in charge would let such a dangerous product onto the market. I’ve never had a problem with those hoses, but it seems I might be the only one who hasn’t. Not to even get into the performance motorcycles that come from the factory with braided hose. This genuinely surprises me, because I can’t imagine why insurance companies and product liability lawyers haven’t had a field day with it. A government agency being inept? I have no problem believing that, but overlooked by shady lawyers? I’d think those jackals could sniff out carrion anywhere.
Anyway I had to find out more, so I looked up the NHTSA TP-106-10 standard and had a read, (see it http://www.nhtsa.dot.gov/staticfiles/DOT/NHTSA/Vehicle%20Safety/Test%20Procedures/Associated%20Files/TP-106-10.pdf). This standard was issued in April of this year, and sets the testing and performance standards for brake hoses. The list of tests is pretty impressive and seems complete, including:
LABELING INSPECTION
12.A.2. CONSTRICTION TEST
12.A.3. EXPANSION TEST
12.A.4. BURST STRENGTH TEST
12.A.5. WHIP TEST
12.A.6. TENSILE STRENGTH TEST
12.A.7. LOW TEMPERATURE RESISTANCE TEST
12.A.8. END FITTING CORROSION TEST
12.A.9. OZONE RESISTANCE TEST
12.A.10. WATER ABSORPTION TEST)
12.A.11. BRAKE FLUID COMPATIBILITY TEST
12.A.12. HIGH TEMPERATURE IMPULSE TEST
12.A.13. DYNAMIC OZONE TEST)
12.A.14. TRACER CORD IDENTIFICATION
All these tests refer directly back to SAE, ASTM and other standards bodies requirements for testing, materials, and performance. As a quick summary the two most compelling problems mentioned in our discussions would covered by the tensile and whip tests. These tests are conducted with pressurized hoses:
Tensile Test - ( A ) Conduct the slow pull test by applying tension at a rate of 1" per minute. The assemblies shall withstand a minimum pull of 325 lbs. ( B ) Conduct the fast pull test by applying tension at a rate of 2" per minute. The assemblies shall withstand a minimum pull of 370 lbs.
Whip Test – This is as the description implies, whipping the hose back and forth. “The time duration for the whip test shall be 35 hours at a machine speed of 780 to 800 rpm.”
If you read the full text these aren’t sloppy, easy tests. I could imagine that a brake hose that was too short for the application would fail if yanked lock-to-lock between the hard line mount and your caliper, but other than that, which is misuse, I don’t see anything in the test being insufficient for the application. Same with the whip test. That test, by the way, is what separates the “DOT” hoses from “race” hoses. To pass the Whip Test the hose manufacturers install a rubber or plastic collar from the fitting up through the first two inches of the braided part of the hose. That gives that section of hose some support so it doesn’t go into shear against the fitting. No plastic reinforcement means “race” hose.
I know more now, but still have no idea how so many brakes could have catastrophic failures on public highways without provoking a firestorm of lawsuits. That’s OK, I guess, there are a lot of things I don’t understand.
I did read something interesting that I didn’t know, about the metric system. Did you know we’re on it? From the introduction to this standard:
“Section 5164 of the Omnibus Trade and Competitiveness Act (Pub. L. 100-418) establishes that the metric system of measurement is the preferred system of weights and measures for trade and commerce in the United States.”
I wasn't aware of that, so it was very interesting news. Especially since every measurement in this standard was exclusively in Imperial values.
I had braided hoses on the front of my car when I 5-lugged it. They were very stiff. When checking for left-right freedom of the struts before connecting the tie rods, I noticed the stiff braided hoses caused the end of the hard lines on the body to flex.
Fearing the hard lines may fatigue from the flexing, I replaced with standard rubber hoses. The hard lines don't flex now.
With performance motorcycles you'll notice that the hose is long. It also goes through a small range of motion. It has a very small chance of reaching its elastic limit.
Take that same hose and shorten it up by 3x. Then put it through 3x the range of motion. Like your cars front brake line. There is a much higher chance of it reaching its limit.
If I have some SS hose at the house I'll do a little show and tell.
One other thought. The front brake reservoir is attached to the handle bars. The only motion the line would see is vibration and the up and down movement of the front wheel.
The rear brake is mounted to the frame and is operated by your right foot. The only motion that line would see is vibration and the up and down motion of the rear tire.
An automotive line sees right, left, up, down and vibration all at the same time.
You got me there.
BTW - Your avitar is outstanding.
OK, here's the show and tell I talked about. This is high quality aircraft stuff. It blows the doors off of any automotive line.
The line on the left was cut using a high speed grinder. You'll notice it's nice and round. The line on the right was cut using very sharp diagonal cutters. You can see how the line is tweaked and no longer round. The line was stressed beyond its elastic limit. Kinking the line would do the same thing. The line would be weakened at that spot. Continued movement will eventually cause the line to fail.
Attached thumbnail(s)
So..................... Does anyone make a SS covered rubber line? Bling and saftey.
Sorry, but how is that relevant? You've deformed one with side cutters, but how would that ever happen in automotive use? No automotive hose that is the correct length will be put into a position that it can be flexed to the point that it "kinks" the way you indicate. If it's possible to do that with the hoses on your car it means they're too short, and that would be misuse. You cut the other with a high speed wheel, the way it should be cut. I really don't understand the comparison or your point.
If you have the correct length brake hose it should never be put into the position where it can be extended so much that it's stressed. Certainly never stressed longitudinally as much as the NHTSA tensile test. The only thing a correct length hose should ever see in automotive use is movement, and NHTSA "whip" test is intended to be an extreme case of exactly that. Both braided stainless hoses and standard rubber hoses pass that test.
Do you know of any formal test data that indicates that teflon hose, covered or not, has flex performance that's inferior to rubber? If so, how much? That would be relevant.
By the way, the NHTSA test mentioned above was released in April of this year, 2008. So it's a brand new standard. And further the NHTSA database (it's on their website) shows no investigations of any brake hoses from failures in use. IE no complaints. Zero. So if you've had a catastrophic brake failure I'd request that you do every automotive enthusiast a favor and register that with the NHSTB so nobody innocent dies. Their complaint number is (888) 327-4236.
The purpose of the picture was to show that the hose isn't as resilient as rubber. We've all cut rubber hose before. You dont have to baby it with a high speed grinder to avoid damaging it. Cut it with an axe and the end will still be round. I believed that was relevent to the discussion.
Folks that have experience working with SS hose and those that have had failures are sharing their experiences with you. Take it or leave it. If you think they're the best thing since sliced bread go for it.
I've run them on race cars and had good luck with them. The pros outweighed the cons. When driving a car on the ragged edge every extra bit helps. I personally wouldn't run them on a street car. The line is inferior to rubber in the resilience department.
It seems odd to me that in all those DOT tests there isn't one that actually tests the line on a car. Did I miss those?
Didn't mean to bring up a sore subject.
Now that you all have me scared about the SS DOT lines I was going to use, I'll trade them for a set of rubber ones.
I did not know/think about many of these valid points. flying rocks, road debris, dirt inbeded in the braid...I can see why they are less durable.
the pros: stiffer pedal "feel" and bling.
First off I'm not trying to be argumentative. Please read all of this before you get pissed off.
The steel braid isn't holding the hose in that position. After the braid is cut it doesn't hold anything together. That's the reason for the tape on the line cut by the grinder. It holds the braid so it doesn't unravel. The braid is like a Chinese finger puzzle. I could peal the braid back to show you the tweaked teflon but I'd poke my finger 150 times just so you could say it's irrelevant.
A complete assembly is only as strong as its weakest part. The picture shows the weakest part. The inner teflon. The fact that you don't find the picture relevant baffles me.
Any material can flex infinitely as long as it's not flexed past its elastic limit. The simple truth is that teflon reaches its elastic limit before the stock line. I could cut a stock line with a diagonal cutters and show you it's still round. But again I'm afraid you'd feel it was irrelevant.
How is installing the line on the car irrelevant. How does the DOT check the hose for proper length and measure bend angles that might be encountered? The labratory tests are irrelevant.
I've worked with engineers for many years. They design it and I build it. I've tried to explain this simple fact to them many times. Just because it looks good on paper doesn't mean it's going to work in real life.
I hate to say my patience is exhausted. I suppose yours is too. How about we agree to disagree.
Both types of hose are TUV certified.
If you want to fix the problem call (888) 327-4236 the next time you see a failure. If you don't give a shit then don't call. No one ever HAS called, so I guess it's not really that much of a problem anyway.
Stay with the D.O.T. approved SS lines.
I also had a near miss with the racing version...ZB
Please correct me if I'm wrong, but it appears to me that the ONLY difference between the currently available "racing" SS brake lines and the "DOT" lines is the sticker, certifying that the product so labeled has been tested in accordance with the DOT's specs and procedures. Costs money to do that, and the end user is gonna pick that up. If they can sell 'em to racers, that not-inconsiderable cost can be avoided, and their per-piece profit will be higher.
The Cap'n
Geeezzeeee...you guys follow the link....
http://www.youtube.com/watch?v=yQ4CweGjUVM
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