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FD Fuel Line upgrade question

Old 09-01-15, 11:54 AM
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FD Fuel Line upgrade question

So here it goes. I'm looking into upgrading the stock rubber fuel lines in the engine bay and in the rear by the filter/charcoal canister. They are old and have seen better days. I would like to use AN fittings from the hard line to the upgraded stainless steel however, i can only find adapters that fit 5/16 to AN -6 (apparently an AN -5 is rare). Do you guys suppose using larger diameter "soft lines" would adversely effect the fuel system, recalling the fuel would "bottle neck" at the hard lines.

I cant really justify upgrading the stock hard lines to 3/8th as it doesn't meet my power goals.

Thanks in advance.

-Dave
Old 09-07-15, 06:31 PM
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Be careful about AN lines, I had my FC converted over to them and I had one split lenthwise (internal rubber) on me, got lucky it was when i was getting the car out of winter storage and i was watching stuff real close.
Old 09-09-15, 11:21 AM
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Huh, no kidding. I was always under the impression that braided SS line was actually more resilient than oem rubber. Good to know i guess.
Old 10-02-15, 02:33 AM
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I just up graded a aftermarket fuel rail and injectors - etc using proflow AN fittings and braided lines - I would recommend asking a shop for help, If your running a aftermarket ECU this set up and maybe a larger intake pump would help you with giving you plenty of fuel - When using on the track i would even add a surge tank from Turblown.com

Fuel rails and braided lines just setting up




pro flow fittings before put on motor
Old 10-05-15, 11:25 AM
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How did you connect the hard lines to the SS braided lines on your set up? Ive seen guys use compression fittings but i think there only rated for 50 psi or something, and i feel like that's cutting it close.
Old 10-05-15, 11:53 AM
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You can use 5an tube nuts and sleeves. The end of the hard line needs to be cut off and flared using a flare tool with 37* angle. Then you can use 5an to 6an adapters. It's a pretty common solution.


FD Fuel Line upgrade question-image-4124276404.png



FD Fuel Line upgrade question-image-833556304.png
Old 10-06-15, 11:09 AM
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Yup. I think your right, tube sleeves and flared tips are the way to go. This is now on my to-do list.
Old 10-06-15, 11:17 AM
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I used this Rigid brand flare tool. Very easy to use and I recommend it.
Amazon.com: Ridgid 41162 Model 377 Flaring Tool: Automotive Amazon.com: Ridgid 41162 Model 377 Flaring Tool: Automotive
Old 10-12-15, 11:50 AM
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Definitely jealous of all those AN fittings
Old 04-07-16, 02:51 AM
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Originally Posted by Andre The Giant
You can use 5an tube nuts and sleeves. The end of the hard line needs to be cut off and flared using a flare tool with 37* angle. Then you can use 5an to 6an adapters. It's a pretty common solution.


Attachment 566814



Attachment 566815

can anyone please point me into the right direction with regards to the 5an to 6an adapters

thank you in advance
Old 04-07-16, 09:23 AM
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XRP 991907. Link below says 8-4, but is really 6-5

XRP - 991907 AN 8 Male to AN 4 Male Flare Reducer - Aluminum
Old 04-09-16, 12:02 PM
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ive always used ss and they never failed me tbh. i don't know what that guy is talking about his splitting.
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