[Schroeder]

I've just started looking at AN fittings and rigging up my new 1/2" fuel system properly. I mapped out my fuel system last night with the filters, pump, reg, etc. I got a count together of what I think I'll need. I can not believe how much they charge for these fittings. I will probably see what JIC fittings I can get from work instead of buying the AN fittings for an arm and a leg. That being said, I will still have to buy some fittings. I am curious as to what you guys do to go from AN hose to hardline though. For example, I will run braided 8AN out of my tank and over the axle of my car. Once I get to the rear frame rail I will switch to some of that 1/2" aluminum hardline from summit. Which connectors do you use for this transition? Do you recommend these:
http://www.ebay.com/itm/8-AN-Female-...b12a22&vxp=mtr

or these:http://www.ebay.com/itm/Speedflow-8A...c89487&vxp=mtr

....in conjunction with these (imagine that the side port is plugged): http://www.ebay.com/itm/AN-8-AN8-Mal...409a28&vxp=mtr

I also am confused about what to do at the carb duel fuel inlets from my regulator. In my mind I should run 2 separate 8AN lines from the regulator to either carb bowl with a unit like this for maximum flow: http://www.ebay.com/itm/8-AN-Dominat...d15129&vxp=mtr

However, most of the "duel" carb feed lines you see look like this:http://www.ebay.com/itm/Barry-Grant-...1255b7&vxp=mtr

That to me is not "duel" feed. That is a single inlet wye'd into 2 separate lines. What do you guys think?

On a finale note, I'm wondering where I should be putting my near-carb fuel filter. Instructions say put it between the pump and the carb. I have a reg between the carb and pump. I was thinking it would be wise to filter fuel after the pump and before the reg. This way the fuel would be filtered for the carb and the regulator, thus protecting them both.

From my reg I would like to run 2 8AN fittings to feed either side of my TRUE DUEL carb line, a fuel pressure gauge, and my 1/4" return line.

Is any of my thinking flawed here? I'm still not sure I have these AN fittings figured out where I can minimize my use of them since they're so freaking expensive.

Here is my mocked up fuel diagram. Maybe it's useless chicken scratch, but I thought I'd share.

[Schurkey]

1. If that's a return-style fuel pressure regulator, you're going to need WAY larger than 1/4" return plumbing.

2. Use less hose, and more metal tubing. ESPECIALLY on the pressure side of the fuel pump. Metal tubing is lighter, less expensive, and more durable than hose. Given a choice, I'd use NO hose from pump to carbs; certainly not more than 8" to provide some flexibility when removing carb(s) for service. The return side can use as much metal tubing as the supply side--just enough hose to connect to gas tank, and at the engine to allow for engine shake.

3. Given a choice, use Teflon-liner hose such as Aeroquip 2807 or equivalent rather than rubber-liner hose on a fuel system. Rubber-liner hose is much more porous leading to "gas fumes" in the garage over night.

4. The "wye" style fuel feed at the carb has been used successfully on a bazillion "high performance" vehicles. How much fuel can you push through a needle 'n' seat assembly? I'm not saying that there are applications that won't appreciate a separate plumbing system from regulator to carb...but I'd think they'd be very unusual; and never driven on the street.

[gunmetalgray67]

Schroeder,

Its insanely expensive to do all AN fittings and hose...I should know I did it. I thought it would look cool and I needed to replace my whole fuel system anyway. I have all black anodized fittings and Pro-Lite 350 black hose. I used -8 for return line and -10 for everything from fuel cell to regulator then -6 to carb "fuel log".

Mine goes fuel cell--fuel filter with shut off (100 micron)--Aeromotive A1000 pump---line to front of car--inline fuel filter (40 micron)---regulator---line to fuel log attached to carb.

If you can do hard line it will be a lot cheaper. How much power are you making? My engine made 620 HP on the dyno and I use a single feed line into my 950HP double pumper with no issues.

Schurkey,

3. Given a choice, use Teflon-liner hose such as Aeroquip 2807 or equivalent rather than rubber-liner hose on a fuel system. Rubber-liner hose is much more porous leading to "gas fumes" in the garage over night.

I have had a "gas fumes" in the garage smell since I got my car running. My whole fuel system is lined with Earls Performance Pro Lite 350 hose...from the fuel cell to filter, pump, to regulator, to carb fuel log and the whole return line also. Its synthetic rubber.

I have traced the whole system and never find any leaks yet hours after the car is in the garage the whole hose smells!! Wife is not happy.

I cannot find any part # 2807 at Summit. Is it PTFE lined braided stainless steel? Any help appreciated.

Thanks

[lust4speed]

All braided hoses except for the Teflon have a finite shelf life, and a pretty short one in the grand scheme of things. Something in the order of 8 years is about all you want to go. You can see normal hose deteriorate, but braided hose hides the problem until fuel or oil is squirting out the braids. On the flip side, I've got one car that I installed aluminum tubing in 1985 and it is as good now as the day I installed it.

I'd say your plan is way too complicated, and agree that you want to maximize hard line. While it is a little more work under the car, there's no reason not to run an aluminum line directly from the pump all the way to the front up to the regulator. If you have a large 100 micron filter with the proper AN male fittings cast in, it can be connected to the suction side of the pump with just one adapter fitting (or 2 depending on the pump).

Return line needs to be sized to the output of the electric pump. Using -8AN tubing for the feed and return line on even a Mallory 140 pump will probably have a residual pressure of about 6 pounds. Going to a -10AN return line will reduce this to less than 2 pounds. Pressure loss going to the regulator isn't a big deal since there is extra pumping pressure and the regulator compensates by its nature. The return line has the same internal resistance, but must flow freely enough to keep the overall pressure low. After installing a larger -10AN return, the pressure was still around 2psi. Looking things over I had a straight shot coming into the regulator, but had a 90 degree fitting on the return. By just swapping out the position of the regulator and making the return the straight shot, the free flow pressure dropped another 1/2 pound.

Also, the way to tell your return pressure resistance is to screw the adjustment screw while the pump is running and just see how low you can get your free flow pressure.

[Schurkey]

Originally Posted by gunmetalgray67

Schurkey,

3. Given a choice, use Teflon-liner hose such as Aeroquip 2807 or equivalent rather than rubber-liner hose on a fuel system. Rubber-liner hose is much more porous leading to "gas fumes" in the garage over night.

I have had a "gas fumes" in the garage smell since I got my car running. My whole fuel system is lined with Earls Performance Pro Lite 350 hose...from the fuel cell to filter, pump, to regulator, to carb fuel log and the whole return line also. Its synthetic rubber.

I have traced the whole system and never find any leaks yet hours after the car is in the garage the whole hose smells!! Wife is not happy.

I cannot find any part # 2807 at Summit. Is it PTFE lined braided stainless steel? Any help appreciated.

Thanks

Aeroquip 2807 is a model number, not a part number. It's also an "industrial" hose. As far as I can tell, the same stuff is sold as Aeroquip "TFE" or "PTFE" Racing hose, like this stuff: http://www.summitracing.com/parts/aer-fcc0620

I suspect, but can't confirm, that if you buy it from an industrial hose supplier, you'll pay less money. Or, you could buy the Summit-brand rather than the name-brand stuff.

Yup, porous fuel hose will stink up a garage overnight, without leaving a drip on the floor.

[Cliff R]

For the fittings I just go to our local hydraulic parts supplier that makes up hoses and buy the 3/8" NPT to 1/2" "AN" fittings. Most components (fuel pumps, filters, sumps, etc are 3/8" NPT or 1/2" NPT threads.

For Q-jet fuel filter housings we remove the inverted flare threads and drill/tap for NPT threads.

I use and prefer the "push-loc" hose these days, and buy the 1/2" fittings and hose from NAPA. It's a little less expensive if sourced out on-line, but they stock what I want and no waiting. With push-lock hose/fittings, you can make up an entire fuel system in minutes, vs hours using the Aeroquip screw together type fittings......Cliff

[HWYSTR455]

Compression fittings are a touch more expensive than AN tube sleeve/nuts, but understand you then need a female to female adapter. I think it still ends up being roughly the same cost in the long run. In my case, looking back, I feel I would have saved some time and frustration by using the compression fittings.

Not all fittings are made the same. Some of the less expensive ones have internal steps, neck down, and/or in some other way cause a restriction. Some areas it doesn't make much of a difference, in others it can make or break. For example, pump input and output fittings.

I recently used the Jegs brand fittings, they were fairly inexpensive, and were of acceptable quality.

In some areas it's acceptable, and less expensive, to use the push-lock type hose. Areas that are out of the way etc are good examples, no one will ever see it anyway, unless maybe they crawl under the car. The newer push-lock hose is the submersible type, and don't believe it suffers some of the historic seep or fail issues traditional braided hose does. (I'll let you know in 10 years what my experience is!)

When it comes to return and feed line sizing, to be safe, and avoid controversy, make them the same size. Can't really go wrong that way.

Same with the 'dual feed'. Not only is there a needle and seat to think about, but the line to the pump is only one line, right?

A lot of mechanical pumps are internally regulated, so a regulator after is really only going to serve as a bypass junction for the return.

Considering what your intent is for moving to a new fuel system, you may want to consider going to an electric pump only setup. Think of the push/pull comparison, especially with rubber lines. You have a section of rubber line that gets 'sucked', the longer it is, the more chance of it being restricted by sucking. That doesn't happen on a push setup. And sometimes, you don't know it's leaking on a suck system either.

Don't forget your pickup assembly in the tank, which in most cases is 3/8 or smaller. If your tank is the OE one, seriously consider replacing it. New EFi ready tanks, with sumps and better flowing pickups are like $225. And in the future, if you ever choose to go EFi, you'll be ready.

And finally, a chance for a plug on a fairly recent thread on this topic:

http://forums.maxperformanceinc.com/...d.php?t=749614

.

[Captainofiron]

To the OP:

I dont know if you knew this or not, but true AN fittings are so expensive because of the tighter tolerances (they are meant for aviation/aerospace) the JIC are less expensive because these tolerances are looser (class 3 versus class 2 threads for example)

Here at work we use a TON of these type of fittings, and I just want to echo what every one is saying, maximize the tubing runs and minimize fittings, doing this you will reduce weight, and limit potential leak points.

One benefit to the 37 degree flare is if you take care of the cone, you can reuse them for a long time, versus compression fittings which can mare the tubing and will need new ferrules eventually.

And on a final note, look at Amazon, they have various AN fittings, or you could look at a more industrial site like Mcmaster

[Cliff R]

Another side note. NEVER under any circumstances use any Teflon tape anywhere on the fittings, it is not needed and will find it's way into the pump, filter(s), and carburetor.

The cheap fittings are fine for making up a fuel system, but the thread above is correct, they are not as close on tolerance, course/rough on the NPT threads, and heavier. If you want light, pretty, and larger holes in them, then get the anodized stuff from Summit or Jegs, or you can Google it up and save some money on Ebay or Amazon......Cliff

[Lee]

HOSES TO THE CARB: Make these long enough to allow pulling the float bowls WITHOUT removing the lines. This makes jet changes quicker and easier.

Look into the nylon braided push-lock hose, or even the non-braided. These are the newer hoses, and are designed for use with alcohol-containing fuels. The 250psi hose is STOUT, you'll have to put the end of the hose in boiling water for several minutes in order to fully "push" it into the place. I recently did a system with the 150psi line (supplied with a FAST EFI kit) and it pushes on MUCH more easily.

I used the aluminum fuel line one time, and it was a pain. It kinked very easily, and you had to buy even more fittings than if you just ran the flex line the entire way. MUCH higher chance of a home-flared tubing end springing a leak than a quality AN fitting, as well.

[Schroeder]

Originally Posted by Schurkey

1. If that's a return-style fuel pressure regulator, you're going to need WAY larger than 1/4" return plumbing.

2. Use less hose, and more metal tubing. ESPECIALLY on the pressure side of the fuel pump. Metal tubing is lighter, less expensive, and more durable than hose. Given a choice, I'd use NO hose from pump to carbs; certainly not more than 8" to provide some flexibility when removing carb(s) for service. The return side can use as much metal tubing as the supply side--just enough hose to connect to gas tank, and at the engine to allow for engine shake.

3. Given a choice, use Teflon-liner hose such as Aeroquip 2807 or equivalent rather than rubber-liner hose on a fuel system. Rubber-liner hose is much more porous leading to "gas fumes" in the garage over night...............

Wow, there is a lot of good stuff here. Thanks for all the replies guys.

I gotta start by clarifying my application. This a 600hp/600ftlb 461 stroker with 305CFM ported KRE heads by SD. I'll be running 1.52 rockers, TII intake, and some 950 holley 4150 carb. THIS IS A MECHANICAL FUEL PUMP WITH DEAD HEAD REGULATOR. I have the RobbMC fuel sender unit, so my pickup is just a tube with .5" diameter.

I am very aware that AN fittings are made to tighter tolerances, but I use the JIC fittings at work every day and know they're perfectly capable of carrying liquids as we run liquids through them and push barb hose everyday. We use 300psi pressurized push barb hose at work. What are compression fittings though?

As far as return lines go, RobbMC told me that 1/4" hose will suffice for the return with this regulator.

Cliff, it's interesting you mention the push

By the way, I realize my drawing may not be clear, but I had aluminum hardline used for all the straight shots in my car to and from pump. I'm going to look at the push hose option because I KNOW I can get those fittings for nearly nothing from work. I will have to look for submersible, petroleum-compatible hose though. Any good links with a cheap, good product would be appreciated.

[TransAm400]

Somebody recommended these guys awhile back. I have no personal experience with them but you may want to check out their prices.

http://www.anfittingsdirect.com/

[Captainofiron]

Originally Posted by Schroeder

Wow, there is a lot of good stuff here. Thanks for all the replies guys.

I gotta start by clarifying my application. This a 600hp/600ftlb 461 stroker with 305CFM ported KRE heads by SD. I'll be running 1.52 rockers, TII intake, and some 950 holley 4150 carb. THIS IS A MECHANICAL FUEL PUMP WITH DEAD HEAD REGULATOR. I have the RobbMC fuel sender unit, so my pickup is just a tube with .5" diameter.

I am very aware that AN fittings are made to tighter tolerances, but I use the JIC fittings at work every day and know they're perfectly capable of carrying liquids as we run liquids through them and push barb hose everyday. We use 300psi pressurized push barb hose at work. What are compression fittings though?

As far as return lines go, RobbMC told me that 1/4" hose will suffice for the return with this regulator.

Cliff, it's interesting you mention the push

By the way, I realize my drawing may not be clear, but I had aluminum hardline used for all the straight shots in my car to and from pump. I'm going to look at the push hose option because I KNOW I can get those fittings for nearly nothing from work. I will have to look for submersible, petroleum-compatible hose though. Any good links with a cheap, good product would be appreciated.

compression fittings come in alot of different styles, the most common are what I will call the home plumbing style with a brass ferrule that smashes against the tubing and nut to seal


there are also swagelok

parker (both double and single ferrule)



and many many more

that being said, go with a JIC fitting, with those you can get the system leak tight better and with more repeatability than a compression fitting which require 1/4 turns and clocking
especially since you said you use the JIC at work

[Schroeder]

thanks a lot capn. those compression fittings look like a huge PITA. I think I'll stick with JIC/AN. I am looking at using push bard stuff with the JIC fittings because, as I said before, we have them at work, and they're much cheaper than all the AN fittings I would still need to hook fittings to hose. I do not have easy access to AN style hose to fitting connectors, but push barbs are plentiful. They work well too. I'll let you guys know how it turns out or if I have any more questions. Thanks.

[HWYSTR455]

The compression fittings I used were simple, cut the hard line, clean the end, slide the fitting on and tighten. Done.

http://www.jegs.com/i/JEGS+Performan...10552/10002/-1

http://www.jegs.com/i/JEGS+Performan...10553/10002/-1

Tube nuts are like $1.75 ea, get a 2 pack for $3.50:

http://www.jegs.com/i/JEGS+Performan...10383/10002/-1

Need the sleeves too, but still cheap at a $1.50 ea:

http://www.jegs.com/i/JEGS-Performan...10393/10002/-1

The straight -8 push-loc fittings are only $6, totally affordable:

http://www.jegs.com/i/JEGS+Performan...10052/10002/-1

The push-loc hose is like $3 a foot, but you don't need much if you do most in hard line:

http://www.jegs.com/i/JEGS+Performan...02021/10002/-1

Aluminum 1/2 line is a buck a foot:

http://www.jegs.com/i/JEGS-Performan...15101/10002/-1

Think maybe this is being over-thought/engineered, it a lot easier than it's being made out to be.

.

[Schroeder]

hanks a lot HWY. ill look over all those options. I think I am going to go with push lock stuff because I can get it for free or for very low costs. I have made this out to be a big deal but I am unfamiliar with the AN fittings and such. I will still be using the AN fittings in the engine bay as it looks way nicer than cheesy push lock stuff

[HWYSTR455]

Np, and understand, that's what I did, used AN/braid in the engine compartment, push-loc in the stuff that can't be seen. Still have to go from hard to braid or push hose, really the only 2 options are compression or flare it for a tube nut. The ones I've used were cake, and looked good.

Like I mentioned, just went through this but with an electric pump, my first post has the URL to my how-to, you can see how I ran the hard lines.

Hope I helped some, and good luck, post once you've got it figured out and installed, sure all would be curious how you made out.

.

[Schroeder]

Im thinking of running all push barb hose to and from.the engine bay. Cheap from work and very, very durable. Close to a 7/8" OD but I think I can deal with that. Here is a linknto the stuff we use. Says its compatible with fuel. Great stuff. What do u guys think? http://www.eaton.com/Eaton/ProductsS...se/PCT_1025624

[Schroeder]

What about flaring hardlines for AN fittings? Standard flare tools will not work since they are 45 degrees. Isn't a double flare much better than a single flare too? double flaring tools for AN fittings are super expensive too. It is not something I want to spend my money on considering I'll probable never use it again.

[Captainofiron]

Originally Posted by Schroeder

What about flaring hardlines for AN fittings? Standard flare tools will not work since they are 45 degrees. Isn't a double flare much better than a single flare too? double flaring tools for AN fittings are super expensive too. It is not something I want to spend my money on considering I'll probable never use it again.

yea you need a special flaring tool for the 37 degree sealing cone used on the JIC/AN fitting specification.

If I remember right, Rigid makes a good one, but its pricey.

really for the pressures you are running I would just go with a single flare. We have a 1500 psi Helium system with all AN/JIC fittings and it is leak tight.

If I remember right there is a thread on here about flaring and tubing, I posted on there the procedure our techs use to flare tubing. Its not super hard, just time consuming and easy if done with the proper tools.

if you are using aluminum tubing (I think you said you were), it should be easy, the hassle is 300 series stainless steels, because they work harden and it gets tough to form the flare because the steel at the bend starts to get stiffer and stiffer the more you deform it