Need advice on a fuel cell

[Slow old poop]

I've been looking at the latest Summit catalog, and see that I can buy a fuel cell for as litle as $89. I definitely need something to solve my fuel pickup problem on long lefts, and this seems cheaper than a surge tank and another fuel pump. Might even save some weight.

Anybody got any advice on buying and installing a fuel cell?

Summit has drag race, street rod and sprint car fuel cells (with the pickup on the right), ranging all over the place in price.

A few questions:

What fuel pump works in a fuel cell? Specifically, will my Walbro fit in? Or do I need to buy a separate pump?

Mount it in the trunk or under the trunk? I was thinking that if I mounted it inside, it might be possible to smooth out air flow under the back of the car.

How big? They come in 5-22 gal sizes. I was figuring that an 8 gal might be enough for NASA races. If we run One Lap, that might pose a problem. If we do, I can always put the stock tank back in.

Any advice?

Rich

 

[DarthBulk]

Your goals are different than mine, but I can help with some of your questions. I managed to fit a 20 gallon fuel cell in the back of my Talon, but I did it by cutting the floor of the trunk out, building a custom mounting bracket for the fuel cell, and then building a firewall box up into the trunk area to keep everything fuel related out of the passenger compartment. A 20 gallon fuel cell is definitely the largest that I could fit in there, and that was tight. It seems your needs will be satisfied with something a lot smaller.
Unless you order a custom fuel cell, it will most likely be set up for an inline fuel pump. There will be AN -8 or so fittings on the bottom of the fuel cell, on the side that you choose. You can plumb those to just about any inline fuel pump.
Something else to think about is the venting of fuel cell. I plumbed one of the top vents on the fuel cell to the original car vent system.
Another issue is the fuel level sensor. I chose to have my fuel cell equipped with a GM 0-90 ohm sensor, which of course does not match up with the Mitsubishi fuel level gauge. So you will have to get an aftermarket gauge to display your fuel level, if that is important to you.

 

[drivemusicnow]

I've looked into this quite a bit, and have a rather wide variety of information regarding the issue. I've also chosen not to go that route.

First things first, you need to read the NASA CCR regarding fuel lines, fuel tanks etc. I know you're only Time trialing, however I think i remember you wanting to do W2W later? Anywho, there are a lot of rules about the thickness of metal, type of metal, lines through the interior, incorporating the cage, etc.

ATL is essentially the leader as far as fuel cells go. Unfortunately they're also ridiculously expensive. Figure an 18 gallon cell, with bladder, and top plate will run you almost 900$

I personally think running the stock tank to a 70$ surge tank, and then mounting an external walbro pulling from the bottom of that surge tank (total cost of about 130$ is going to be my method of solving the issue. Just seems to be the best idea for my application. (we should both do OLOA some year... just for kicks and grins. Be a DSMTuners team That way we can haul an entire parts car around with us for when we break )

 

[Greg Collier]

I run an ATL 13 gallon fuel cell with a surge tank for cornering. The exterior fuel pump is an MSD with a stainless steel braided main feed with gas pressure meter in the cockpit. My cell is cut through the rear truck with the fuel pump located where the old gas tank was. If I remember correctly it was over a 45-pound weight savings, and it added a better balance to the cars weight until I start to run low on gas. That's when the rear wing helps to keep the car in check.

As Greg has already mentioned you can’t use any fuel cell. It must be foam lined and per the CCR list of approved cells. You wouldn’t want a cheapo one anyway in case you were in a crash, God forbid, car fires suck… been there done that!

You want a 13-gal minimum.

 

[Greg Collier]

As I've looked at the costs of cells, surge tanks, stainless steel braided fuel lines, and fuel pumps, a descent setup would cost in the neighborhood of $1200.00 to $1500.00. Fortunately I was being sponsored by Dave Turner Motorsports at the time so I paid (2) stickers...

 

[logic]

Rich, those el-cheapo Summit cells are marketed pretty much exclusively at drag racers who don't have the same stringent requirements SCCA and NASA do; if that's the route you're thinking of going, you'd actually be ahead of the game just welding up something yourself, and throwing a bladder in it.

My solution (which hasn't seen the light of day yet, sadly) was to go with the 15 gallon aluminum version of Greg's cell, and two externally-mounted Bosch 044 pumps drawing from each rear corner. My hope is that it'll be good enough to avoid the need for a surge tank. Now I just need to plan out a series of idiot lights to let me know about pump health and pressure at various locations in the system.

Total cost so far is disgusting. The cell was about $550 from OGRacing, the pumps were another $450 from Jay Racing, and then the replacement aluminum top plate after I mangled the steel one that came with the cell (MEASURE TWICE, CUT ONCE, DANG IT) was another $150 from Anglo-American. That doesn't even cover the cost of all the braided line and fittings (heck, the Y-fitting alone came in around $40, if memory serves), and the materials for the tube frame for mounting the cell to (plus all the time needed to weld, test fit, and assemble the whole mess). So Greg's 2-sticker cost sounds pretty good to me at this point.

But, do it right, or do it twice. Isn't that how it goes?

Honestly, having looked at Erica's 1g fuel tank, I'd probably just do a surge tank and external pump, rather than going with a fuel cell on a 1g AWD. The 2g AWD fuel tank is just too ugly for words, though.

 

[Slow old poop]

Rich, those el-cheapo Summit cells are marketed pretty much exclusively at drag racers who don't have the same stringent requirements SCCA and NASA do; if that's the route you're thinking of going, you'd actually be ahead of the game just welding up something yourself, and throwing a bladder in it. <snip>
Honestly, having looked at Erica's 1g fuel tank, I'd probably just do a surge tank and external pump, rather than going with a fuel cell on a 1g AWD. The 2g AWD fuel tank is just too ugly for words, though.

That's what this forum is for, getting information like this. Who knew?

What all you are telling me is that the Summit fuel cells are crap, won't pass NASA rules, and legal cells are bloody expensive.

So it's back to the surge tank, eh? What are my options there? I've seen a GM-type drop-in tankand pump around here somewhere.

Can the tank be pulled and surgically altered to accommodate a bladder or baffling?

Will my Walbro work with any of these solutions, or do I need another pump?

Keep this good info coming, please.

Rich

 

[Greg Collier]

Here ya go Rich: http://cgi.ebay.com/ebaymotors/ws/e...RK:MESE:IT&viewitem=&item=280050084462&rd=1,1

 

[Elvenhome21]

What i am planning to do, I have a 8 gallon fuel cell with the bolt on cap (round style)

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and
off of two of the bolts make a bracket that bends straight down 3/4x1/8 aluminum that goes almost all the way to the bottom of the tank. Then with a walbro or what ever pump you are using, put a hose clamp or something similar around the pump and the bracket. Along with a piece of sheet metal formed into a circle (it can even be like a foldgers can) with a couple notches cut out of the bottom, I would cut some sort of slits in the back so i could get the hose clamp around it to mount it to the bracket. With the fuel feed and return lines your going to have to use bulkhead fittings and with the return line feed it into the surge tank. I will mock up a real setup tommorrow and take a picture of it but this drawing should be some help for now. CLick on the picture and it will get bigger

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[Greg Collier]

What i am planning to do, I have a 8 gallon fuel cell with the bolt on cap (round style)

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and
off of two of the bolts make a bracket that bends straight down 3/4x1/8 aluminum that goes almost all the way to the bottom of the tank. Then with a walbro or what ever pump you are using, put a hose clamp or something similar around the pump and the bracket. Along with a piece of sheet metal formed into a circle (it can even be like a foldgers can) with a couple notches cut out of the bottom, I would cut some sort of slits in the back so i could get the hose clamp around it to mount it to the bracket. With the fuel feed and return lines your going to have to use bulkhead fittings and with the return line feed it into the surge tank. I will mock up a real setup tommorrow and take a picture of it but this drawing should be some help for now. CLick on the picture and it will get bigger

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[/URL][/IMG]

Cool design... I hope you're talking about the new and improved plastic Foldgers can and not the old style tin one that will rust... Also if you have two feed lines you'll need a check valve on each side to close off the end that's leaning in the turn or the surge tank won't work. Keep in mind that if you use it for a sanctioned race series like NASA or SCCA it'll have to be SFI approved and stuffed with foam.

 

[Slow old poop]

What i am planning to do, I have a 8 gallon fuel cell with the bolt on cap (round style)

1. Eight gallons is cutting it pretty close. I go through about 5 gal of race gas in a 20 minute session. That means you better top it up before each session, or you will be toast.

2. If it's a foam-filled fuel cell, you shouldn't need a surge tank.

Rich

 

[drivemusicnow]

Rich,

I've been debating this for the past year or so. I originally thought I could do an intank surge tank, but after seeing the gas tank out of the car, and playing around with some cardboard, I just don't think that it will work. The stock tank is baffeled, however it just doesn't work very well.

I'm going to be using an external surge setup. It's going to go something like this:

1 Gallon Aluminum Fuel tank, with a -6AN "drain line" fitting at the bottom, -6AN feed line on the side near the top, and a return line at the very top.

I'll have the in tank Walbro HP feeding this surge tank, and then another "in line" walbro 255HP using the -6an line from the bottom of the surge tank, pushing towards the fuel rail. This will eliminate any fuel issues, and it has a minimal cost compared to other methods. YOu can get a 1 Gallon SFI approved tank for about 80$ with the fittings arleady in it. Then the extra fuel pump and fittings ends up bing like 150$.

I'm going to start with just running the walbro pickups that move with the fuel and close off when they suck air, and if that doesn't work (2 of them are like 20$ I think) I'll move to the surge tank idea.

 

[Greg Collier]

If it's a foam-filled fuel cell, you shouldn't need a surge tank.
Rich

Yes you do... because the physics is still the same.

 

[DSMunknown]

Additionally, it may interest you to look through the thread below, Rich:




http://www.dsmtuners.com/forums/showthread.php?t=245607

 

[Elvenhome21]

greg: if the pump is intank you only have one pressure line and one return line. but the foldgers can was just an example, my dad was saying a HI-C can would work from back in the day, I have never seen one so i didn't know what size it is, but the foldgers smaller size metal one (4") is the size i was meaning. I would use Aluminum flasing from Menards or home depot instead (easier to cut).

SlowPoop: 8 gallon tank would be small but there is no other track that would use that much fuel. I would like to get a 12-16 gal. bladder cell but I have the tank here so I will put that on the list for next year.
I am a circle track racer so it is just common practice for me to top the fuel off anyways (got to make weight)

If your buying a cell don't get a bottom draw, many sanctions don't allow them. You might also have to put a steel can around the cell, 18-20 gauge steel. that might just be a circle track rule along with a bladder.


I have coil over springs for sale any rate availible Email me [email protected]

 

[Greg Collier]

As long as you're retaining enough fuel in the can at the lowest point of the tank. The concept being when your pulling enough g-s through a turn that there's no starvation. Some of the major sweepers that I race on can gobble up a lot of fuel in a short period of time. The surge tank accepts all of the fuel going into the turn while the check valve on the opposite side closes, then vice/versa going in the opposite direction.

 

[97eclipseNT]

hey greg where can you pick up one of the check valves you useif you are runing a setup like that?

 

[Elvenhome21]

You could probably use these if you mounted it correctly but you would only need this with an external pump steup. i will keep looking for the correct check valve.
http://www.speedwaymotors.com/xq/aspx/paging.yes/dept_id.58/display_id.451/qx/Product.htm

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[logic]

Once it's all back together, I'm using these (the -10AN version):

Link

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Another nice-looking one is the Aeromotive version:

Link

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The basic idea is that it's a one-way valve: gas flows through in one direction, but not in the other. In my setup, I've put a check valve on the outlet side of both fuel pumps, which should both retain pressure in the combined line to the rail (they Y together right after the check valves, so if one pump isn't picking up fuel, the other should be able to, thus keeping pressure in the line) and protect each pump from cavitations introduced by the other. That's the plan, anyway.

 

[drivemusicnow]

Why in the heck would you us a -10AN line for fuel? That's entirely gigantic, and especially out of the pump it just doesn't make any sense.

I'm running -6AN lines from the pump to the fuel rail, and think that for my goals it is more than I need.

 

[logic]

Actually, you caught me in a lie; it's actually -8AN, not -10AN. The layout of the system I have right now is -10AN from the two fuel cell pickups to each filter, then -10AN to each pump, then -8AN out of the pumps to the check valves, then a Y fitting back up to a combination of -10AN braided and 5/8" hard line to the rail, feeding four 1600s. A combo of -8AN braided and 1/2" hard line runs back to the cell for the return.

If you're curious, what drove this setup choice was a combination of future planning and cost considerations. Specifically for the dual pumps, I believe it will effectively eliminate the need for a surge tank, and a pair of -044 pumps was cheaper than a single comparable Aeromotive unit. Combined with the right idiot lights on the dash, I've got a bit of redundancy built in as well, although that was a secondary consideration (redundancy increases complexity). As for fuel volume, well, that's the future-planning part of the setup. With line choice, materials availability drove that to a certain extent, but I also gave a nod to the volume of fuel being transferred; a pair of -044s will push an enormous volume of fuel at idle, and both the feed and return need to be sized appropriately to handle that.

Disclaimer: I'm not throwing this out as a recommendation of any kind. Anyone should be able to see that this is overkill, but the components were selected to work together. I really only posted the original note to give 97eclipseNT and Elvenhome21 a good source for check valves. Check Jegs too; they carry similar stock.

I should also point out that the check valve that Elvenhome21 posted is a fuel cell vent that doubles up as a check-valve in the event of rollover; basically, the ball remains down in the cell under normal circumstances, venting pressure to wherever you choose to route it. If the car flips, the ball settles, and prevents the out-flow of fuel from the tank. A good fuel cell should have one of those (my ATL cell came with one as part of the filler plate), but that's not the kind of check valve you want in-line in your fuel system; you're looking more for something like what I posted, which serves as an in-line check valve.

 

[Elvenhome21]

logic: exactly what i was looking for

Drive: -10an isn't really that big for a single fuel line, I am using half inch copper from the tank to the fuel rail.

 

[drivemusicnow]

I guess it depends on what type of power you're looking to make. Larger lines mean more pressure drop from pump to rail. THis means that to get your 43.5 psi fuel pressure at the rail, the fuel pump is having to try and push say, 45 psi. Not a big deal, until you add in 25 psi of boost on top of that. Fuel rail pressure of 68.5 psi would be 71-72 psi from the pump.

I chose -6AN line based on removing the fuel filter outlet restriction, and eliminating a point of failure (15 year old hard lines). I've seen 800hp cars use -6 line, so I figured my measly 500hp at the crank should be fine with this.

I guess if you have the fuel pump capacity (like you both apparantly do) there wouldn't be any significant downside to running larger lines, as they would supply plenty of fuel at almost any pressure.

 

[Elvenhome21]

the only reason i am running it, is ss braided is quite expensive above -8 and my fuel rail has -10 so 1/2 works perfect with a 5/8 flare fitting from home depot, I had like 20 inchs of -10 braided for a flex section on the motor, so total cost was like 10 in copper, fitting, solder. Plus copper doesn't have a problem running e85.