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01-02-2008, 04:49 PM
I'm getting ready to install my new gas tank in my 1978 Camaro and I'm trying to figure out how the heck to connect the fuel lines to the tank.
The tank has been modified with a baffled pickup and in-tank pump. To do this a section of the top of the tank was cut out and a plate was installed in it's place to hold the pickup, sending unit, and the return. This plate is about 1" lower than the top of the tank, to allow some room for fittings.
The supply, return, and vent fittings are all 3/8" NPT and face upward. I need suggestions on what kind of fittings to use to make the 90 degree turn and change from NPT to A/N threads.

The vent line I'm not too worried about, since it doesn't have to be A/N and doesn't have to flow liquid.

I know you shouldn't use tight bend fittings for supply and return, due to restriction, but I'm not sure I've enough room for larger-radius fittings, especially if I have to install an adapter between the bungs and fittings.

I am also unsure of what kind of hose I'm going to use. Some people have said that XRP hose does not leak gas fumes like some other brands do, but when I called XRP they said that any CPE hose will do that, so I should use Teflon hose if that's a concern.

I have been considering running steel line from the bungs to the front of the tank, so I can connect/disconnect the lines a lot easier if needed and I could even run hard line from there, but I still run into the issue of going from a 3/8" NPT bung to the line and making it face the correct direction.

So, I think I've rambled enough, what do you guys think?

70 Chevelle
01-02-2008, 05:20 PM
http://store.summitracing.com/partdetail.asp?autofilter=1&part=SUM%2D220652&N=700+4294924496+4294839052+4294849624+115&autoview=sku

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01-02-2008, 05:52 PM
That was one of the types of fittings I was looking at, but I was told that they do cause some restriction. It would definitely simplify things if the restriction is low enough.
This would be another option, except for the type of hose: http://store.summitracing.com/partdetail.asp?part=RUS-612100

CarlC
01-02-2008, 06:44 PM
That's a nice fitting, if it will fit.

What are the engine and fuel pump specs and location?

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01-02-2008, 07:18 PM
Engine is a 400 small block, big solid roller cam, Bowtie Vortec heads, and a Ram Jet intake manifold. Compression is 10 or 10.5:1, I forget now, and it's got .037" quench. I was told 500-550 hp at 7,000 rpm, and those are not supposed to be "magazine" numbers. I think the intake might be a restriction, so I may try getting it Extrude-honed, but that's well into the future.

The fuel pump I'm not completely sure about. It's a high pressure (65 psi?) 225 lb/hr Walbro pump. I think it is a Ford application, though the tank paperwork says LS1. The pump is in the tank.

I'd like to find a fitting like the Russell part, but for Teflon hose, but I haven't found one yet. For standard braided stuff, yes, but not Teflon.

My dilema is to go with a forged fitting, which has a tight radius and will restrict flow, or to go with a CPE hose that may leak fumes. Unless, of course, somebody knows of just the right fitting.

uwntsumrtII
01-03-2008, 09:25 PM
check these guys out as well. they make high quality stuff.

http://www.fragolaperformancesystems.com/

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01-06-2008, 09:31 AM
I need to make a correction: The bungs are 1/4" NPT.
Also, I compared the stock tank and lines to the new tank, and I have 1-5/8" from the top of the bungs to the top of the stock lines. So, any adapter and fitting combinations cannot be taller than 1-5/8".

Here's a picture of the top of the tank. The sending unit is still taped up, so you can't see much, but you can see how the it is recessed into the tank a little bit.

megaladon6
01-06-2008, 11:20 AM
http://store.summitracing.com/partdetail.asp?autofilter=1&part=EAR%2D923106ERL&N=700+4294849624+4294906676+4294906716+115&autoview=sku

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01-06-2008, 04:53 PM
Yeah, yeah, yeah. I can search Summit too. Is there anything like that fitting, but using bent tube, and for teflon hose?

Hammered
01-06-2008, 05:07 PM
Russell has a pipe to AN fitting that uses a tube, but if it's a typical setup you also need to worry about having enough separation between the supply and return fittings to be able to thread both in. If you look at the high flow intank pumps, they typically have small openings so I wouldn't worry about 6-8" of smaller ID lines and fittings. It's the cumulative pressure drop you need to worry about.

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01-06-2008, 05:36 PM
That explains part of why they would sell me a high pressure, 255 lb/hr pump and use 1/4" NPT fittings. I was wondering why they didn't use something bigger, since they recommend 3/8" feed line and 5/16" return (stock sizes).

70bird
01-06-2008, 06:26 PM
I see your tank is finished, so I know you probly don't want mod it unless you need to, but here is the tank from Rick's in my 2nd gen.
https://static1.pt-content.com/images/noimg.gif (http://img409.imageshack.us/my.php?image=lowresfirebird107mp4.jpg)
https://static1.pt-content.com/images/noimg.gif (http://img125.imageshack.us/my.php?image=lowresfirebird108fz7.jpg)



Wouldn't be too much work, since it is still out of the car to do some thing similar if you can't find fittings to clear.

Assuming you are not gonna use a transverse muff. it has mucho room to route fuel lines any way you like. And if you are concerned with tight radius causing restriction, just go over size on the line.

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01-07-2008, 10:39 AM
That's what you get for assuming! ;) I am going to be using a transverse muffler.
I guess I'll have to get the tank up in there and see what kind of room I've got. Should be fun.

70bird
01-07-2008, 11:13 AM
That's what you get for assuming! ;) I am going to be using a transverse muffler.
I guess I'll have to get the tank up in there and see what kind of room I've got. Should be fun.
:guilty:

CarlC
01-07-2008, 02:16 PM
Watch out for the teflon fittings. They neck down to under 1/4". Aeroquip -8 standard fittings do as well. The current setup in my car has the Aeroquip standard fittings only on the pressure side of the pump and I have had no problems.

Given these restrictions, here's my gameplan for the new setup. Use as many 3/8" hardline runs as possible, and have EFI specific AN short hoses made for the fuel tank - body and front frame - engine connections. It's more work, but in the long run I think more reliable and easier to repair.

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01-08-2008, 05:35 PM
I had been looking into XRP hoses/fittings, and they seem to have a decent ID on the fittings. Actually, right now I'm waiting to see the new hoses my boss is going to get for his race car. He is replacing his XRP stuff with Goodridge, IIRC. The new hoses are supposed to be lighter and more flexible.

I'm on the same page as you with the hard line. I intend to run flexible only where I have to, at the tank and at the engine.

The one other thing I am considering is using a 90 degree NPT-to-flare fitting that uses a 45 degree flare, and running hard line from that fitting to the front of the tank, across the front and toward the back, like the stock lines did, and installing the fuel filter on the side of the frame rail. This extra complication should allow me to install a newer OEM-style fuel filter and skip the flex hose in the rear.
I'll still need flex hose up front, but it'll be two fewer sets of fittings.

Hammered
01-09-2008, 10:57 AM
I did what Carl is planning to do and the fittings alone probably cost over $300. I also had to run two short sections of hardline from my tank bung/pump assembly to the front of the tank where I picked up flex lines that attached to hard lines bent up like the factory did. I'm running 1/2 and 3/8