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Braided steel fuel lines

When I install my new fuel regulator, I'm thinking that I may just take the opportunity to switch out my fuel lines for braided steel.

What size hose, fittings, etc do I need? How much more difficult than standard fuel lines and hose connectors are they to work with? Are they worthwhile?

Thanks!

Oh, and what's a good source?

Why would you though. More money, less flexibility, better looks, safer. I personally don't think we run high enough fuel pressures to denote the need for braided fuel lines. So many run their cars daily and on the track without them that I personally wouldn't go that route.
Some of the high horsepower guys have done it though. Like 1badmx5.

I guess partly to dress up my engine bay. I've seen guys with them. I just never thought about them because I was always farting around with my FMU and I didn't want any added hassle. Now that I'm dumping my FMU, they seem like something I can just install and enjoy the added benefits, if any, without having to fuss around with them too much. Now I'm wonderring what benefits there might be before I decide stricly on aesthetics.

They do look good i'll give them that. Outside of what I said already I don't have anything to add.

No worries. Much appreciated. To bling or not to bling....:bigtu:

I think all the fuel line in the miata engine bay is 5/16".

I can see the point for bling, it looks cool. If you could convert everything to AN fittings instead of barbs that would be even better, I find push on barb fittings to be a pain in the ass.

I assume you would have to cut the ends off the existing hardlines and use special 37* Flare AN fittings at that end, then you could run like -5 line for it all.

If you want some quick answers call up anplumbing.com and talk to their Tech. He's a friendly guy but I'd swear he's hyper active on the phone.

from the miatapower mailing list (ie not written by me):

Quote:

Originally Posted by Ed Cheal

I've copied my notes on this project below. Some of this is specific to the '99; the replacement fuel pulsation damper and extra T adapter to connect it probably aren't needed on earlier models (with return fuel system). IIRC, I bought most of the parts from RacerPartsWholesale, what they didn't have I bought from Summit (I always try RPW first).

***********

Replumbed the stock fuel lines using -6AN Aeroquip Startlite hose and fittings:

1) removed stock pulsation damper (the one that was near the right upper shock mount in the engine compartment, just below the STB) and the stock fuel lines from the hardline that pops up into the engine compartment (near the pulsation damper)

2) cut the end off the stock hardline, slid on a -5AN flare nut and sleeve (both steel, AER-FBM2755 and FBM3571), and put a 37 deg flare on the end using a flaring tool

3) put a -5AN to -6AN adapter (steel male-male) on the flare nut (AER-FBM2755)

4) put a -6AN T adapter on that (aluminum, F-M-M, AER-FBM2282)

5) attached a Marren Hydraulic Pulsation Damper (www.injector.com, Part # 0201, $114) to that T using a Russell -6AN female to 3/8NPT male adapter (RUS-614226)

6) attached a second -6AN T adapter to the first T adapter (F-M-M, AER-FBM2282)

7) ran two -6AN Startlite hoses with aluminum hose ends to the two ends of the Vishnu fuel rail; the rear hose has a 45deg hose end at the T and a straight hose end at the fuel rail; the front hose has a 130deg hose end at the T and a 30 deg hose end at the fuel rail

8) attached the hoses to the fuel rail using 1/4"NPT to -6AN 90deg adapters (AER-FBM2034). I also fabricated an aluminum bracket to support the first T adapter (the fuel hardline was a bit "top heavy", mostly due to the Marren fuel damper).

update: ed cheal's cardomain: http://www.cardomain.com/ride/354727/9

Any pictures of this setup kicking around anywhere?

you'd like that wouldn't you. reload. i added it to my post.

Man. That installation seems a bit involved. I was thinking i could just slap braided steel lines where I have rubber lines. He does mention not having to replace the pulse dampener in earlier models. I guess this is goint to take some serious thinking.

Thanks!

Give me a second I'll go take some pics of mine. I believed there AN6 fittings. brb

"If you want some quick answers call up anplumbing.com and talk to their Tech. He's a friendly guy but I'd swear he's hyper active on the phone."

Or...I can just go there and ask in person. The shop is 20 minutes from my apartment. :bigtu:

This is what I did. Remember this IS a DIY install so I didn't bother buying the "official" regulator adaptor from the Miata fuel rail to AN fitting. I just welded a steel AN fitting to the stock regulator flange after I cut the regulator off with a wizzwheel. The feed is still just a hose. I did this to the return to get the 1:1 regulator installed. (Gotta love 550s and a stand alone) :bigtu:

EDIT - The Regulator, lines, and fittings all cost me $300 !! Seems expencive but stable fuel pressure is reflected in my nice flat fuel maps. It pays to do it right I guess.

So the aftermarket FPR you installed required steel braided lines and AN fittings, or did you just decide to go that route? The Synchronic is supposed to be a drop in replacement so I need to check on its capacity for an aftermarket fuel line set up.

Quote:

Originally Posted by FHS (Post 101403)

No, it's really not that bad. Your car doesn't have a pulse dampener, and I don't see the need to use the -5an to -6an adapter. The only extra thing we'd have to do is the return line.

so for the supply you'd need a flare to -5an, 5an hose, 5an T, 2 5an hoses, 2 npt to 5 an fittings

for the return you'd need a flare to -5an, 5 an hose, and a npt to 5 an fitting
Not that bad. Maybe we can get someone to put a kit together. Micheal?

Quote:

Originally Posted by y8s (Post 101398)

you'd like that wouldn't you. reload. i added it to my post.

You da man cool guy!

Quote:

Originally Posted by FHS (Post 101425)

I'm pushing 200+hp so I needed a good regulator. It just happened to come with those sized fittings so I used them. I think thats all it normally uses since the AN fittings that screw into the fpr are o-ring sealed. I'm sure you could find barbed adaptors for just sticking hoses on it but it looks high performance this way. =)

A note on barbed fittings and teflon lined high pressure hose... The barb will cut the teflon liner and the hose will blow. Use hose fittings without the barbed edges or file down the barbs to a smooth rounded edge. Good thing I had a dream, the night before, that I burned up my car and threw a fire extinguisher in it. That day I blew the fuel lines but nothing caught on fire. :x:

This is something that I have wanted to do, but I have never found any -5AN fittings anywhere.. And the -5AN hose I have only found a few places and its a bit pricey... I just used rubber pushlock on my dual feed and it works fine, just not quite as bling..
-Michael-