New fuel lines and maybe a Fuel Cell

Rusty67

Rusty67

20+ Year Stangneter :roc</strong><span class=
Dec 3, 2002
3,749
37
109
LA, CA
#1
Ok, so I have this fuel leek in my car. Its because the hard line was broken and a PO at some point repaired it with rubber hose which of course degrades over time. Guess where the brake is ? Thats right, the drives side frame rail... you know the LOWEST point on the car where the engeneers ran a damn fuel line... that was brilliant.

Anyways, I'm going to be pulling my motor soon (soon is a euphanism) so I figured what the hell, why don't I just replace it with some brand new Stainless Steel line. What I was thinking of doing is running some 3/8" fuel line up underneath the transmission tunnel right next to the 3/16 brake line that is already there. I was actually going to run a pair of lines in there so that if I ever wanted to go EFI (which I provably will eventually) it will be there, ready to go.

What I want to know about the fuel line, are there any safety concerns when it comes to running a fuel line there ? once the trans is bolted down, it isn't going to come up and whack the fuel lines so I'm not worried about that and the diff certainly isn't going to come up and bite into the lines. What I am more specifically worried about is vapor lock. Will the heat from the rear of the engine create any issue with vapor lock in the lines ? I doubt it would. If anything, pre-heating the fuel would most likely improve the combustion because I don't think that the heat from the back of the engine would be hot enough to create vapor lock but that is why I'm asking. Would it be an issue for either a carbed or an EFI engine ?

On to the fuel cell section.

I was thinking of using a universal fuel cell. I am not going to spend God know how much on a fuel safe cell. Summit racing sells some nice aluminum ones and some steel ones as well. I don't really know much about fuel cells. I did a search and turned up some ways to mount them. It does not seem to be very difficult to get one to fit in the stock hole as long as they are the right dimensions.

What I am interested in as far as fuel cells go is, should I get a cell with a bladder and if so what kind of bladder ? Something else that interests me is an in tank pump. Can I just use something like a late model fuel pump ? If I switch over to an electric pump I don't want to hear the bastard and an in tank pump is more reliable. If I do eventually go EFI then I will have to go with an electric pump so I figure if I am seting this all up now I might want to switch now and use a fuel pressure regulator to take care of the extra PSI from the pump. And of course, if I were to put an electric pump in I'd make sure to use an inertia switch ;-)

Sorry for the long post but details are a must IMO.
 
#2
Good questions.

I have recently been researching fuel systems myself. As for the steel line in the trans tunnel, there isnt a problem I see with that, but why not just run it up the passenger side frame rail and then into the engine compartment from that side in front of the firewall, rather than coming in through the fender? Thats what I have planned on doing....right into a FPR. If, for some reason, you ever need to service your fuel line, you will have to drop the trans, right? I dont know where the line would be in the back of the car, but will the driveshaft be a concern if it comes loose and bounces up and breaks the line? What about heat from the exhaust?

As for fuel cells, I too, was looking at the fuel safe items...but...$1500? Come on. I ended up looking at the ones from summit for about $200 + a little extra for a sending unit. The only issue that I could see was you will have to do a little fabbing and I dont think you can run a filler neck...not that i could see anyway. I would go ahead and get one with a bladder, why not, ya know? I doubt you will NEED one unless you are doing some heavy cornering. As for material for a bladder, again, I dont think that will make a difference either.

I, personally, like external pumps. If something goes bad, it is easy access to fix.

If you decide to go with 3/8" SS line, let me know, I think i have a new roll of it in my garage that I bought from summit some time ago. I think it is going to be too small for me.

-Shane
 
#3
I remember a while back someone said that some sanctioning bodies would not let you run it through the trans tunnel. IMHO it is a bad idea to run the fuel line in the trans tunnel because of the drive shaft if something where to go wrong it could open the line and supply the needed sparks at the same time.
 
#4
Allcar, I wasn't going to run the fuel line in from the fender, I was going to run it straight up the rear of the firewall. I figured it would be easy to service any rubber line, all I'd need to do is take the air cleaner off. Also, if I switch to EFI, I think the fuel rails have connectors toward the firewall so that would take care of that for me.

As far as running it through the trans tunnel, I figured if I put 2 drive shaft safety loops in (1 front, 1 rear) it would keep anything like that from happening. I've got quite the solid drive shaft and upgraded u-joints but I'm still going to put safety loops in. I suppose if the actual shaft broke then I would be screwed, but I don't intend on making the kind of power that would brake my current drive shaft. If my drive shaft broke it would be from an accident. Jester, do you think it would still be a serious concern to run it down the tunnel with thse safety loops in ?

The reasons I want to run an in tank pumps are reliability and sound. External pumps can be heard, I don't like that. My 2000 v6 Mustang and my dad's Bullitt have factory in tank pumps and you can't even hear them when they are running. That is what I want. As an added bonus, in tank pumps do not wear out nearly as fast and are not subject to the same heat issues that external pumps are. As for the filler neck, I would just cut a hole in the cell once I had it mounted and have a friend weld in a plate I could cap off or bolt a filler neck to. That shouldn't be difficult at all.
 
#5
I've got to chime in here, since I use Fuel Safe cells in every car I build. The bottom line is that you get what you pay for. Just because the inexpensive aluminum cans from Summit are called "fuel cells" just like the Fuel Safe ones doesn't make them equivalent -- far from it. The Summit cells are just an aluminum box to keep your fuel in. There is little, if any, safety benefit to using such a cell. They are typically used when fabbing a race car where an OEM tank won't fit, has the wrong capacity, etc. I see no advantage to using most of these cells over a new OEM gas tank, unless you just want to look cool.

Fuel Safe cells are a similar aluminum can containing a super-strong urethane bladder which is then filled with open-cell foam. The bladder has nothing to do with fuel sloshing! It is there so that when you get rear-ended by an SUV or whatever and your fuel tank gets crushed, there is a deformable structure to contain your fuel instead of letting it all spray out of a ruptured tank. Inside the bladder is a special foam. This helps support the bladder, helps control slosh, and displaces air as the cell empties, providing a less combustible environment.

Next, the two main design flaws in your Mustang's fuel tank are the fact that the tank is the trunk floor (isolated from the cabin by virtually nothing) and the filler is connected to the tank with a rubber hose. In the event of a hard tank-crushing rear-end collision, this hose pops off and fuel is sprayed into your car like a firehose. A rare event, but a possibility. Fuel Safe cells have a large one-way check valve here, so as the tank is crushed it seals itself closed.

So, not all "fuel cells" are created equal. There is a huge difference between a "fuel cell" and a "safety fuel cell". Look at why you want a cell in the first place -- if it's for looks or simply a custom size, OK. If it's for safety, hopefully you now know the difference.

A couple of comments on your other points...

The pressure requirements are so different between EFI and carbed that I doubt you'll find a regulator that will cut enough pressure from an EFI pump to make it work with a carb. Typical EFI takes 45 psi, and most regulators I've used only will go down to 20 psi or so, which is 3 times the pressure you'll want at the carb.

Pre-heating the fuel will not improve combustion! It's the exact opposite -- cooler fuel makes for more better combustion. Look under the hood of a serious race car and you'll see a "cool can" filled with ice where the fuel flows through a coiled metal tube inside.
 
#6
Reen, I highly respect your opinion and thanks for the input. I have not researched fuel cells thuroughly and as such I don't really know the finer points. I understand that not all products are equal in quality or function. The more I learn about a fuel cell, the more I realize that if I put one in, I am going to want a bladder. Summit does sell fuel cells that have bladders in them. Fuel Safe is charging for two things that other brands are not when you buy one that is specific to our cars. The Fuel Safe name and the fact that it is "custom fit" to our cars. I think they are charging too much for these luxuries and I believe I can make a universal cell of decent quality fit. I don't need a name to tell me if a fuel cell is good quality. I can look at the quality of the welds and know if the product is worth my time/money. That being said, I still would like to find a way to put a SAFE fuel cell that will also sustain the performance of the car during hard cornering without braking the bank.

Can you sugest another place to get a universal fuel cell that is reasonably priced as well as performance oriented ?

As for the fuel pump, its no big deal to me if I need change to a different pump if I switch to EFI. If I can't get an in tank pump to do both I'll try to stay with my mechanical pump for now and I'll just load up a fuel pump in the tank for EFI later since I'm almost certain I will eventually put an EFI system in my car.

I'm much more concerned with the safety of positioning the fuel lines in the trans tunnels and I would be most interested to hear your comments on that.

As for the fuel analysis, I don't want to start a huge argument about it but I remember learning in college that a warmer liquid fuel and a colder air charge will make combustion more efficient. Here is some stuff to back that up:

http://en.wikipedia.org/wiki/Internal_combustion_engine
Fuel systems
Fuels burn faster, and more completely when they have lots of surface area in contact with oxygen. In order for an engine to work efficiently the fuel must be vaporized into the incoming air in what is commonly referred to as a fuel air mixture. There are two commonly used methods of vaporizing fuel into the air, one is the carburetor and the other is fuel injection.

I understand how theory and practical application may differ and I have considered this possibility, heating the fuel causes the air charge to warm up and the gains from a warmer liquid fuel are less then the loss created by the warming of the cold air charge from the heated liquid fuel thus causing a decrease in overall efficiency.
 
#8
Unfortunately, I don't have another lead for you for a less-expensive fuel cell. Fuel Safe cells have always worked well for me and they do custom cans to my design, so that's all I've been using.

I will say that while an in-tank pump is nice and quiet, I've had to change it out a couple of times in a Fuel Safe cell and it's a PITA (once the cell has been filled/used).

I've run fuel lines up in the tunnel before and don't see a real problem with it as long as it's good durable line, is away from the exhaust, etc. I guess I feel that damage from a failed driveshaft is less likely than damage from road debris, but I certainly see the point. Then again, I'm always dealing with new, high-strength driveshaft assemblies.
 
#9
Ok, thanx for the input guys. I'll keep looking for some other alternatives. As for the quality of line I would be using, it is true aircraft stainless steel. There is no seam in it an it has been annealed so that it is bendable and flairable, but it is very high quality stuff. I am not the least bit concerned with the quality of this line.
 
#11
allcarfan said:
do the fuel safe cells have a fitting for a return line? are they -06 or -08 on the outlet?

Do you get more tailpipe clearance (like on a gt rear valance) with the fuel safe cell?
Click to expand...
You can get them any way you want. I commonly get them with a -6 AN fitting for the return line and a -6 AN or -8 AN for the feed depending on the application.

I have designed a custom can they make for me that gives the necessary exhaust clearance for a 67-68 GT valance. The standard squared-off cell covers about 1/4 of the opening.

Pics of standard can and mine (on different cars):

stock_can.jpg


reen_can.jpg
 
#13
reenmachine said:
You can get them any way you want. I commonly get them with a -6 AN fitting for the return line and a -6 AN or -8 AN for the feed depending on the application.

I have designed a custom can they make for me that gives the necessary exhaust clearance for a 67-68 GT valance. The standard squared-off cell covers about 1/4 of the opening.

Pics of standard can and mine (on different cars):
Click to expand...


im not sure what you mean by a custom can?? If it covers that much on a 67-68, i bet it covers more on a 66....i wonder though...
 
#18
brianj5600 said:
This would save a grand... http://www.pitstopusa.com/detail.aspx?ID=18910 It would not hide behind the valance, but does look a little manly.
Click to expand...
I've seen similar cells in race cars and they look pretty cool. I'd have to measure, but I think that cell would hang down below the bottom edge of the valance. You'd then have to make it fit your car somehow, there's no sending unit to know how much fuel is in there, and you have to open your trunk to fill it.
 
#19
reenmachine said:
I've seen similar cells in race cars and they look pretty cool. I'd have to measure, but I think that cell would hang down below the bottom edge of the valance. You'd then have to make it fit your car somehow, there's no sending unit to know how much fuel is in there, and you have to open your trunk to fill it.
Click to expand...

Those are valid points, but if you don't have $1500, none of that matters. I have thought about ditching the gas cap anyway. It takes forever to fill my 67, and if the nozzle is not aimed perfect, it takes even longer. Senders can be added to most race cells as well. They are around $100, but you are still $900 ahead.
 
#20
If you wanted to add a fill tube, couldn't you just cut a hole and weld something in place ? If done properly I can't see it causing any structural problems with the cell.
 
You must log in or register to reply here.

Similar threads

Ryu
Fox Fuel Pump Issues After Replacement/Upgrade
Replies
15
Views
218
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
keel
keel
M
01 mustang 3.8 fuel pressure issue
Replies
0
Views
81
1996 - 2004 SN95 Mustang -General/Talk-
Mhaley2006
M
F
2004 Mustang GT – Fuel Pump Not Priming
Replies
7
Views
204
SN95 4.6L Mustang Tech
n0v8or
N
H
Fuel starvation issues, 91 EFI to carb swap. Car dying after 1-3 gallons used. EFI tank, electric fuel pump, bypass regulator. Dual fed carb
Replies
8
Views
720
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
nickyb
nickyb
S
FUEL PUMP ALWAYS ON
Replies
13
Views
171
1996 - 2004 SN95 Mustang -General/Talk-
nickyb
nickyb
Top Bottom
Back
Forums
Menu