Double or single flair on front brake lines, 83 square.?

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john ward

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Found no info, so any recommendations please.
 

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Standard inverted 45° double flare for SAE brake lines. Nothing else will be safe.

Metric brake lines are inverted 45° double flares. Made several feet of these up on various Subaru, Toyota, Datsun, along with VW Rabbits, Jettas, Ghias, and Beetles.

Metric fuel lines on the higher pressure VW K-Jetronic Mechanical Fuel Injection had ISO bubble flares but a lot of other early fuel injection systems used 37° & 45° double flares or just beaded lines with good clamps.

Maybe I'm just feeling old and grumpy today... but... Flair and Flare have very different meanings. Flair is one of those pufta words.
 

bucket

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Standard inverted 45° double flare for SAE brake lines. Nothing else will be safe.

Metric brake lines are inverted 45° double flares. Made several feet of these up on various Subaru, Toyota, Datsun, along with VW Rabbits, Jettas, Ghias, and Beetles.

Metric fuel lines on the higher pressure VW K-Jetronic Mechanical Fuel Injection had ISO bubble flares but a lot of other early fuel injection systems used 37° & 45° double flares or just beaded lines with good clamps.

Maybe I'm just feeling old and grumpy today... but... Flair and Flare have very different meanings. Flair is one of those pufta words.

Well I dunno about all those furrin rides, but GM's metric lines were almost always bubble flare. Just thinking about all the lines I've made for them makes my knuckles hurt.
 

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What GM vehicles use ISO flares on the brake lines?
Not saying they didn't.

It's not a real good union for high hydraulic pressures... I'm surprised US DOT let em use them on brakes in the US.
I guess you can buy anything including the DOT.
 
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bucket

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What GM vehicles use ISO flares on the brake lines?
Not saying they didn't.

It's not a real good union for high hydraulic pressures... I'm surprised US DOT let em use them on brakes in the US.
I guess you can buy anything including the DOT.

You are getting technical on me, lol. You mean bubble flare? Basically all GM products with metric fittings. If there were any that didn't use bubble flare, I don't recall the application. 80's through the 00's. I haven't done lines on anything after '05 or so. But lots of trucks and FWD cars. I'd hate to know how many I've done. But now that I'm out of the shop, it's not so often anymore. The most recent was making all new lines for a friend's '03 Silverado. Before that was rear lines on my '00 Burb.
 

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ISO (International Standards Organization) or DIN (Deutsches Institut für Normung) flare is a bubble flare. Die verdammten Deutschen came up with them. :p
Inverted 45° is SAE (Society of Automotive Engineers).
The Brits loved 37° flares. Helped a buddy make up several on a Morgan and an MG in his collection. Don't get me started on the odd Brit bolts on those rigs. They had to be right because they were show cars.
Just to add to the tower of babel... Girling brake had their own British non ISO version of the bubble flare and Japanese cars that used JIS (Japanese Industrial Standards) had Metric 37° inverted double flares.

The most recent GM rig I did brake any lines on was my 2000 GMC C2500 T400 pickup and that was just over a decade ago. IIRC that had 45° inverted double flare lines. I'd remember an oddity like ISO flares on my American truck.
The 60's, 70's, & 80's VW's I did brake lines on were over 30 years ago. IIRC they were inverted 45° but I'm questioning my recollection now... I'm not pulling the lines on my 84 GTI apart to find out.

That aside... none of the squares should have anything other than 45° Inverted Double Flare on the brake lines.
 
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bucket

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You're right, all squares should be standard thread and inverted flare. I only mentioned it in case someone was using this thread for info and they had a later truck. I wouldn't put it past GM if some of the very late squares used metric threads and bubble flare somewhere.

Which as a side discussion, bubble flare was far from an oddity. You don't have to believe me, but I promise you there are millions of GM vehicles driving around with metric fittings and bubble flares. If I didn't have a buddy that comes and hauls off my scrap all the time, I'd have a bunch of factory GM lines to show you. They are so common that I keep the bubble/metric line lengths in stock at home. Although I am remembering now that the last '03 truck I did, probably did use standard fittings. I honestly never gave much thought to which style was used because neither style surprised me. I've always just replicated what the factory did without logging in my mind which style it was.

But anyway, I pulled this off the shelf. A front brake hose for an '86 Camaro, and the correct metric/bubble line that matches it. A very common fitting for GM cars.

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Maybe I'm just feeling old and grumpy today... but... Flair and Flare have very different meanings. Flair is one of those pufta words.

...
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Honky Kong jr

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Well I dunno about all those furrin rides, but GM's metric lines were almost always bubble flare. Just thinking about all the lines I've made for them makes my knuckles hurt.
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You're right, all squares should be standard thread and inverted flare. I only mentioned it in case someone was using this thread for info and they had a later truck. I wouldn't put it past GM if some of the very late squares used metric threads and bubble flare somewhere.

Which as a side discussion, bubble flare was far from an oddity. You don't have to believe me, but I promise you there are millions of GM vehicles driving around with metric fittings and bubble flares. If I didn't have a buddy that comes and hauls off my scrap all the time, I'd have a bunch of factory GM lines to show you. They are so common that I keep the bubble/metric line lengths in stock at home. Although I am remembering now that the last '03 truck I did, probably did use standard fittings. I honestly never gave much thought to which style was used because neither style surprised me. I've always just replicated what the factory did without logging in my mind which style it was.

But anyway, I pulled this off the shelf. A front brake hose for an '86 Camaro, and the correct metric/bubble line that matches it. A very common fitting for GM cars.

You must be registered for see images attach


Interesting. I must've not done enough late 80's American cars in my misspent youth.

I got curious and looked around on Google for the odd British-Girling bubble flares I saw once on a Triumph...They have a taper against the ferrule and against the fitting unlike the ISO DIN bubbles that have a flat against the ferrule and bubble against the fitting.

This popped up with more than you wanted to know about the brake line flare fittings.

http://racetrackdriving.com/tech/brake-line-flares-metric-sae-inverted-bubble/

There are a bunch more variations than I thought there were.
Obviously not all Japanese rigs used JIS 37° and not all Brit rigs used British-Girling bubble flares or the odd 37° English but the basics of what to look for are there too.
 
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bucket

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Interesting. I must've not done enough late 80's American cars in my misspent youth.

I got curious and looked around on Google for the odd British-Girling bubble flares I saw once on a Triumph...They have a taper against the ferrule and against the fitting unlike the ISO DIN bubbles that have a flat against the ferrule and bubble against the fitting.

This popped up with more than you wanted to know about the brake line flare fittings.

http://racetrackdriving.com/tech/brake-line-flares-metric-sae-inverted-bubble/

There are a bunch more variations than I thought there were.
Obviously not all Japanese rigs used JIS 37° and not all Brit rigs used British-Girling bubble flares or the odd 37° English but the basics of what to look for are there too.

I did not know there were two different flare angles used on Japanese vehicles. Now I wonder how many times I botched that.
 

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