Flaring Tool....
Thread Starter
Melting Slicks
Joined: Feb 1999
Posts: 2,473
Likes: 10
From: New Paltz, New York USA
Flaring Tool....
Why and when do use a double flair? I am looking into buying a flaring tool to put a flaire on my gas line so I can adapt a SS braided line to it. I see that most flaring sets come with double flaire adaptors. How do you tell what needs a double and what needs a single flair? TIA
1969/1971/2021 Coupes
Joined: Jan 2008
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From: Port Huron MI
St. Jude Donor '09-'10-'11-'12-'13-'14-'15
There is more of a chance to create cracks in the end of the line material when using a single flare technique. The double flare essentially rolls a double wall thickness into the end of the line and prevents that same cracking potential. It (double) also allows for a thicker bead end over a single flare which will in most cases create a better seal against the fittings.
Terry
Terry
Last edited by HOOAH; Mar 22, 2013 at 02:19 PM. Reason: spelling, not smarter than a 5th grader
Burning Brakes
Joined: Dec 2008
Posts: 971
Likes: 45
From: Middlesex NJ
I agree with Terry..brake lines are high pressure and are inverted or double flared. (so are most fuel lines)... keep in mind typical automotive production flares where 45 degree... the fancy -AN (army/navy) flares you find on most aftermarket stainless lines and fittings are 37 degree so keep this in mind with what parts you buy and with what flare tool you buy.
Last edited by mysixtynine; Mar 22, 2013 at 02:16 PM. Reason: edit
Melting Slicks
Joined: Mar 2007
Posts: 2,520
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From: Hinckley OH
I agree with Terry..brake lines are high pressure and are inverted or double flared. (so are most fuel lines)... keep in mind typical automotive production flares where 45 degree... the fancy -AN (army/navy) flares you find on most aftermarket stainless lines and fittings are 37 degree so keep this in mind with what parts you buy and with what flare tool you buy.
Melting Slicks
Joined: Mar 2007
Posts: 2,520
Likes: 11
From: Hinckley OH
everything you need to know about flaring on this youtube page
DIY Bending brake lines - Helpful Tips - YouTube
DIY Bending brake lines - Helpful Tips - YouTube
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
The AN or JC fittings are 37 degrees. Pretty much all stock brake and fuel lines are SAE 45 degree fittings. The inverted flare fittings are also 45 degree. Dont mix and match. There's also the line material to consider and if it's seamless or non-seamless.
Why exactly do you want to adapt an old 7 psi hardline to a high pressure stainless braided? Just for looks?
Why exactly do you want to adapt an old 7 psi hardline to a high pressure stainless braided? Just for looks?
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Thread Starter
Melting Slicks
Joined: Feb 1999
Posts: 2,473
Likes: 10
From: New Paltz, New York USA
The AN or JC fittings are 37 degrees. Pretty much all stock brake and fuel lines are SAE 45 degree fittings. The inverted flare fittings are also 45 degree. Dont mix and match. There's also the line material to consider and if it's seamless or non-seamless.
Why exactly do you want to adapt an old 7 psi hardline to a high pressure stainless braided? Just for looks?
Why exactly do you want to adapt an old 7 psi hardline to a high pressure stainless braided? Just for looks?
Melting Slicks
Joined: Sep 2004
Posts: 2,655
Likes: 19
I guess it depends on year, model, etc... but I think the normal setup was hardline with a short rubber hose from tank to the pump. The original hardline fittings were inverted flair on both the carb and pump fittings. Those are double flair, 45 degree fittings. Safer, simpler, and cheaper than stainless braided.
Last edited by Garys 68; Mar 23, 2013 at 08:59 AM.
Race Director
Joined: Mar 2006
Posts: 14,112
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From: Florida
Hard gas lines are the same as brake lines. They should be double flared (45°), same as GM did them. GM used all hard lines for pressure and rubber for suction or depending on the filters, rarely used for return.
Just go to a parts store, get a longer length of 3/8" brake line. It will come with the proper fitting on both ends.
Bend it first and then cut to length, reinstall the last fitting and flare it.
A lot of aftermarket stuff is available in AN (JIC) 37° single flare, but that uses a sleeve under the nut.
Don't mix types of fittings. All your stock stuff is 45° double flare.
Just go to a parts store, get a longer length of 3/8" brake line. It will come with the proper fitting on both ends.
Bend it first and then cut to length, reinstall the last fitting and flare it.
A lot of aftermarket stuff is available in AN (JIC) 37° single flare, but that uses a sleeve under the nut.
Don't mix types of fittings. All your stock stuff is 45° double flare.
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
If you want to do this, do not buy a cheap flaring tool. You might ask at a good local auto parts store (probably NOT a national chain) if they can make up the tube you need. Just measure out the length of each section (if it needs to be bent), the angle and radius of any bends, and what type of flares/fittings you want. Making a simple piece up shouldn't cost as much as a decent flaring tool.
For low pressure fuel line, a good quality compression fitting is fine to connect from the existing line to the new one.
For low pressure fuel line, a good quality compression fitting is fine to connect from the existing line to the new one.
Instructor
Joined: Dec 2009
Posts: 195
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From: Chesterfield Virginia
If I remember correctly from a previous post this is for an Edelbrock carb without an internal fuel filter, correct? What’s your plan for the fuel filter?
To answer your original question; double flair if your using an NPT fitting (45 degree) and single flair if your using an A/N fitting (37 degree). NPT fittings (45 degree) are good up to 3000psi. A/N fittings are good to 5000psi (A/N fittings use a ferrule to strengthen the single flair). Your fuel line is 4 to 8 psi, both are overkill, one more than the other. Certain aftermarket carbs require A/N fittings.
Stainless braided lines are rubber inside and in my opinion less safe because you won’t see the rubber deteriorate.
Steve
To answer your original question; double flair if your using an NPT fitting (45 degree) and single flair if your using an A/N fitting (37 degree). NPT fittings (45 degree) are good up to 3000psi. A/N fittings are good to 5000psi (A/N fittings use a ferrule to strengthen the single flair). Your fuel line is 4 to 8 psi, both are overkill, one more than the other. Certain aftermarket carbs require A/N fittings.
Stainless braided lines are rubber inside and in my opinion less safe because you won’t see the rubber deteriorate.
Steve
Race Director
Joined: Jan 2002
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From: No Where USA
If you are looking for a 37 degree flaring tool, Summit has one for under 30 bucks. I had to run some brake line and fuel lines to AN fittings on my GTO. I only needed it for a few flares or else I would have gotten a better one. It worked for what I needed it for. Remember if youy are going to use a 37 degree flare you also need to buy some tube nuts and sleeves.
Instructor
Joined: Dec 2009
Posts: 195
Likes: 0
From: Chesterfield Virginia
Richard, use this paper by Lars as a guide: http://www.lbfun.com/warehouse/tech_...uel%20Line.pdf
That's what I used to build mine
GF481 has been replaced by GF652, I wrote GM parts division when I was building mine.
Steve
That's what I used to build mine
GF481 has been replaced by GF652, I wrote GM parts division when I was building mine.
Steve