I am considering replacing the old tank, with a new one that is modified to acccept an inside fuel pump that would be accessible from the trunk floor as was mentioned is the set up on the LE Mopars.( I think I have those initials right). Runs was the inpiration for this.

Anyway, before I do anything, or purchase anything, I would like to get a discussion going here. I would like to discuss as many options as possible with the pros and cons. The current set up is a stock tank with vent and return nipples JB welded in place. The main supply line is 3/8" but is tapped into the original old 5/16" sending unit outlet. The return line is the original, stock 5/16" line. The vent line runs forward and into the intake. No room for a charcoal canister. The supply line feeds the stock machanical pump, and that in turn feeds a surge tank made from a large truck fuel filter, which then feeds the electric fuel pump which sits on the passenger side inner fender.

I would like to do away with the mechanical pump, and the surge tank if I can come up with a good design for a new tank. I can start with a repro new tank. here are some questions to kick around.

1. Mancini sells specific replacement tanks for all years of A body cars. Does anybody know the diference between the later ones? The years offered are 70-71, and late 71-76. Is one preferable to the other for an EFI in tank design?

2. Someone mentioned the LE Mopars as having a very dependable, and very servicable in tank pump. Any comments on this? Would it provide enough volume? What application am I looking for? ARe there diagrams I can go search for on the internet?

3. Is there a better alternative to a stock replacement tank? Lou mentioned replacement tanks some time ago that had a sump welded in. This would still require an external pump would it not.

4. Runs, what kind of pump did you use? Sorry to ask if you already mentioned, but that info would fit into this thread nicely.

5. I have been told that fuel cells are race only, but have never been told why. ARe they too small for road use? ARe they too hard to fill?

6. I hate the stock gasket set up for the filler pipe. I was considering welding a short pipe into the tank that sticks up through the floor, and then connecting the filler to that with a large hose and clamps. Any ideas where I can get hose that large that is gasoline proof? Is t his safe? Am I recreating the famous Ford Pinto gas tank here? Is there another connector that might be flexible and safe? The gasket system does not seem to seal all that tightly.

I could do all this research on line in a solitary fashion, but it seems like a discussion on this topic might be fun, and yield some otherwise unavailable insight.

The goal is to get a more reliable fuel source, and to unclutter the right front inner fender. It seems that when the car sits for long periods of time, the surge tank can go dry.

Sam

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The A100 van uses sort of the idea you mentioned in #6. When I removed the filler tube and gas tank, a short rubber hose connected the filler tube to the gas tank. I believe the clamps that were used were a large version of the small clamps used on the hose from the fuel line to the fuel pump (think they were called Corbin clamps - but not sure). Can't remember the exact details as I've disposed of my van. The hose is/was available at NAPA

All 1967-1976 A-body gas tanks are the same dimension wise...(depending on your filler neck and venting)

Some differences that I have on hand: (and Dan may be able to fill you in on the exact early 70's versions that have the emmissions routing...like the 70-71's I think have 3 tubes coming out of them in certain cases...)

1967 is hung by one strap going from driver's side to pass side...and typically has no other outlets than the filler tube and the sending unit tube...

1973-1976 are hung by two straps (front to back), has filler neck tube, sending unit, and has one vapor return line tube (5/16"-3/8" in the top of the tank).

-D.Idiot

I went on line and looked at various fuel pump applications, and the choices were mind boggling. Hundreds of styles and makers were available. I don;t know who are reputible makers, and don;t know how to chose an application.
Some models had fuel gauge senders, others did not. Some had plates that looked like they sealed against a mounting surface, and others did not. Some had supply lines and return lines, others did not. I could just make a choice and run with it, but am hoping for a discussion of the pros and cons fof these kinds of things.

Sam

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I kind of wonder if it might be worth looking at a really late A(A)-body fuel tank assembly w/pump ('89-'95 Spirit/Acclaim, '90-'94 LeBaron sedan) to see if it could be readily adapted.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Dan, do you like the fuel pump in these cars? And is there an after market brand that you like. I have seen the fuel pumps on the web for the cars you are talking about, and they look like they could be installed from the top of the tank, through the floor. Does it have the needed capacity for the slant? If so, I will look into that assembly. If the tank does not have the notch for the spare tire well, at the very least, I can start there with the pump, and fit it to a new Dart tank. If that works, I can use a Haynes manual for the plumbing and wiring diagrams. But what about the baffles to keep the fuel pick up from getting uncovered? Any thoughts on where to look for the best design there?

Sam

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is there a reason you don't want to run a frame rail mounted pump? then you could go to a later tank with a return line and keep your plumbing realtively simple. you could also get a weld-on sump from summit. but, i don't know if i would like my fuel lines readily available to the public.

an 89 f-150 has an external fuel pump thats seems robust enough. i have a friend using one on a FI conversion in a samurai and except for being a bit noisy, it works perfect.

zedpapa

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1970 dodge dart w/225 /6 bored .040" over, holley 390cfm w/vac. sec., compcams 252s, clifford shorty headers w/2.5" exhaust w/flowmaster, f-body 11" front discs, aluminum A-833OD, 8 1/4 w/3.21 SG
soon to have 5 gears!!!

I've owned three AA-bodies, and there've been four or five total in my extended family, and — touch wood — we've had exactly zero fuel pump trouble. Never mind, though...I just took a look at a catalogue image of the AA-body tank, and it looks too different to adapt:


I like Walbro pumps, but IIRC you don't want an external pump setup.

If you wanted to adapt an in-tank pump, you might want to see about speccing a pump for the '93-'95 FFV (flexible-fuel) version of the Spirit/Acclaim. Those pumps are made with extra-tough materials throughout to withstand the low lubricity and high corrosivity of fuel that is mostly alcohol.
Yep.
Exactly what made me go "darn..." when I saw the pic of the AA tank.
*shudder*

I'm kinda wondering if you might want to consider a fuel cell instead of a tank, and rethink your objections to an external (in-line) fuel pump.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I had an frame rail mounted pump originaly, and it sounded like Godzilla coming out of the sea, plus, there was a lean fueling problem when I accelerated, or went around a corner with low fuel. Either a sump, or baffles are essential. The sump would be fine, if I could stand the noise. Even the pumps in the tank can be a little noisy. Some noise is actually nice, as you can then tell when it is working.

Sam

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If it amounts for anything I used a 454 fuel pump for a 90's pickup from Federal Mongul and adapted it to the tank. I simply cleaned out my tank, or you could get a simple remanufactured one and weld up the side entrance and make a top hat like mine. If you don't mind cutting into your car, you can make a "hat" and unbolt the entire circle pulling out the pump and sender in one shot through the trunk. To understand what I'm saying you really got to be looking at my pictures. But this seems to be the best option rather than letting a shop build one for $500. I haven't seen if the ones your looking at is adapted for fuel injection, so I plead ignorance there.
One last comment is I saw somewhere that they make a fuel cell that's ready for fuel injection that goes where the spare tire is. Since I don't have a spare or was using it as a show car I thought it would be cool. Good luck overall and defintely go with an intank pump, just my humble opinion.

Yeah...a noisy pump improperly mounted will set up a heck of a racket. A quiet pump properly mounted, on the other hand, is...quiet. It can be done. Zillions of Volvos (amongst many others) had 'em factory installed that way.
How 'bout using an accumulator?
Yep, I do like a quiet "bzhht" so I can tell the fuel pump isn't AWOL. Likewise, I don't mind a slight sing from the rear axle ring & pinion so I know the rear axle is present and accounted for.

(it's 11:16...do you know where your rear axle is?)

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

So lets talk about the Volvo option, and a sump on the tank. That would be the easiest thing to do for sure. How did Volvo accomplish the quiet fame mounted pump? Are Volvos body on frame construction, or unibody. Are there pumps quiet to begin with? If you mount a fuel pump on the frame of an A body car, and you mount it down low, where it must be, then it will end up fastened to the floor, essentially right below the right rear passengers seat, and the entire box of the passenger's compartment becomes a resonator for the sound. It is transfered up the angle braces to the rear shelf, and everything sings like crazy.

I don't mind constructing some sort of special mount for it to make it quiet if that will work. But I hate to reinvent the wheel here, only to find out I re-invented some other dumb-dumb's bad design.

The in-tank pump does not cause me to shudder, once I know I can make it removable from the trunk. That is a project that could be done the remainder of the winter, and installed then in the spring.

I liked your idea of getting a fuel pump for a flex fuel vehicle. I guess that might allow you to add alchohol directly to the tank. I have heard it is a terrific, and fairly cheap octane booster, but that it tears up normal fuel pumps.

Runs, I have studied your set up pictures that you posted. I can't see where the fuel supply and return lines are on that pump. Does that fuel gauge sending unit come with the pump? It seems like that requires a much larger hole in the tank and in the trunk floor. The pumps Dan has talked about look to be smaller in diameter, and are thus maybe more appealing than the big GM pump if they have enough capacity.

Sam

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IIRC, the pump was mounted below the front passenger seat. they are a unibody-design car. the one i did was a 87 or 89. it was mounted on rubber isolaters like the ones used for ignition boxes.

zedpapa

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1970 dodge dart w/225 /6 bored .040" over, holley 390cfm w/vac. sec., compcams 252s, clifford shorty headers w/2.5" exhaust w/flowmaster, f-body 11" front discs, aluminum A-833OD, 8 1/4 w/3.21 SG
soon to have 5 gears!!!

Doesn't Aeromotive make a pump that can be used externally OR internally? I can't find the magazine ad right now (i'm actually quite busy for once) but i'll keep looking tonight.
It sounded like you just mount it into the tank, bypassing all of the original plumbing. You can keep the original sending unit and install the pipes you need.

EDIT: Found it!

Inline EFI Fuel Pump, P/N 11109
Universal inline pump, designed for external mounting.
May be run submersed but custom mounting and plumbing required.
Rated for continuous duty applications.
Flows 325 lbs. per hour @ 13.5 Volts and 45 PSI.
Flexible, 5/16" hose barb inlet and outlet are standard.
Mounting brackets, noise isolator and hardware included.
Suitable for use with Aeromotive Digital FMU P/N 16303.

When installed on its own, the 11109 pump may be upgraded to AN-8 (1/2") with use of the Inlet Adapter Fitting - P/N 15114 (sold separately)

Inline EFI Fuel Pump, P/N 11109

I also checked out their belt-driven pumps... That may be an option

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Chris'
Autobody
Restoration
Service

Nothing very difficult: A quiet, high-quality pump with isolation mounts, with a sound-insulating cover box. On early applications ('70s) they were back by the fuel tank. Location varied in later years; many applications starting in '77 used an in-tank "pre-pump" and an external main pump.
Unit-body.

Me either. Click the red "shudder" text and you'll see what I was shuddering about.
Well, remember the significant upgrades made to the rest of the FFVs' fuel systems: Plastic rather than metal fuel tank, stainless steel fuel hardlines, braided-stainless flex lines, internally nickel-plated fuel injectors, stainless steel fuel pressure regulator and fuel rail, and a fair good bit of "etc". For the amount of alcohol you'd add as an octane booster, most of this would be unnecessary, though. Also remember alcohol's lower energy content per unit volume; don't get so caught up in chasing high octane numbers that you cancel the benefit by lowering the overall energy content of your composite fuel.

Here are some links to look at for external pumps:
Flow & pressure graphs for various Walbro fuel pumps

Pictures and descriptions of Walbro pumps and mounting components.

A less-costly source for Walbro pumps is http://www.fuel-pumps.net/gsl393.html (GSL393 pump — you can append the number of whatever pump grabs your fancy from the graphs above; it's easier than trying to navigate through the site)

Counterfeit warning:
http://www.fuel-pumps.net/walbro-forgeries.html

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一期一会
Too many people who were born on third base actually believe they've hit a triple.