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Mark LaBarre
02-04-2001, 05:33 PM
Has any one installed a fuel cell in their VW? I'm curious if the fuel pump develops enough suction to lift fuel out of the cell or if another pump needs to be used as well.
Thanks!

Ryan Williams
02-04-2001, 10:21 PM
The VW CIS fuel pump does not draw gas very well. When I installed a fuel cell in my G-Production Wabbit, I installed a Carter low-pressure pump (4 to 6 psi) to draw the fuel from the cell. From the Carter pump, the gas passes through a Fram filter to a small surge tank. This surge tank has three fittings on top and one fitting on the bottom. The first top fitting receives gas from the Fram filter; the second top fitting receives the "passby" gas from the CIS Metering Unit; and the third fitting is an overflow return to the fuel cell. The bottom fitting on the surge tank feeds the input to the VW CIS pump. With this arrangement, the VW CIS pump and accumulator work as normal. To meet the SCCA rules, the fuel cell must be contained in a steel or aluminum box held, preferrably, by a steel cradle. There must a be "firewall" between the driver and the fuel cell. In my case, I fabricated a light-weight steel box with a top over the fuel cell and its container. The top is fastened to the "firewall" box with screws. In the center of top, a flip lid allows access to the cap of the fuel cell. If my discription of my pumping system sounds confusing to you, please send your "snail" mail address to [email protected], and I will mail a hardcopy of it to you. Regards.

Jay Frye
02-06-2001, 04:26 PM
Originally posted by Ryan Williams:
The VW CIS fuel pump does not draw gas very well. When I installed a fuel cell in my G-Production Wabbit, I installed a Carter low-pressure pump (4 to 6 psi) to draw the fuel from the cell. From the Carter pump, the gas passes through a Fram filter to a small surge tank. This surge tank has three fittings on top and one fitting on the bottom. The first top fitting receives gas from the Fram filter; the second top fitting receives the "passby" gas from the CIS Metering Unit; and the third fitting is an overflow return to the fuel cell. The bottom fitting on the surge tank feeds the input to the VW CIS pump. With this arrangement, the VW CIS pump and accumulator work as normal. To meet the SCCA rules, the fuel cell must be contained in a steel or aluminum box held, preferrably, by a steel cradle. There must a be "firewall" between the driver and the fuel cell. In my case, I fabricated a light-weight steel box with a top over the fuel cell and its container. The top is fastened to the "firewall" box with screws. In the center of top, a flip lid allows access to the cap of the fuel cell. If my discription of my pumping system sounds confusing to you, please send your "snail" mail address to [email protected], and I will mail a hardcopy of it to you. Regards.

Walt Pucket makes these through his firm Delta Group. Or you can buy them from Tom Fowler @OPM

Bill Miller
02-06-2001, 06:28 PM
You don't just need these for a car (VW) w/ a cell in it. Having an surge tank is a good idea. If it weren't such a good idea, why did VW adopt it in later cars (Fox, etc.)? BTW, I think the surge tank from the Fox works well.

metalworker
02-06-2001, 11:58 PM
Just be careful. At one time a surge tank was considered illegal

MikeM
02-15-2001, 09:06 AM
Hi, I hope someone can answer this question, I am ready to invest in a new fuel delivery system for my 86 GTI 8 valve. I have a fuel safe cell with a surge tank inside(collector), and need to replace everything from the cell to the fuel distributor. The choices as I understand them are: replace all the factory equipment(fuel res, pump, accumulator, lines) or use a (Walbro)high pressure pump, fuel regulator, filter and 6AN braided lines to feed and return the fuel. Both setups are expensive and I don't feel comfortable spending the ~$350.00 when I don't know if it will work properly. Any suggestions on who I might need to talk to? Thanks

[This message has been edited by MikeM (edited February 15, 2001).]

Bildon
02-15-2001, 09:27 AM
Mike,
Once you go the fuel cell route your kinda committed to the complete expense of doing it right. It's very common to have fuel pickup problems once you remove the stock tank and system.

My advice if you have not already removed it would be to utilize the stock GTI setup. It's poly like the Fuelsafe, has a built in surge tank and has low and high pressure Bosch pumps already. It's identical to a common race setup. The only thing different is that there is not a steel box around the cell. But it's up over the axle and so it's protected pretty well. It is a flawless system.

Get new pumps and retain the steel lines to the engine bay. You can get a HP pump for about $150 and the LP pump for <$40.




------------------
Bill Sulouff - Bildon Motorsport
Volkswagen Racing Equipment
www.bildon.com (http://www.bildon.com)
http://www.bildon.com/images/bildon_a3_sm.gif

MikeM
02-15-2001, 10:48 AM
Bill, My stock pump and accumulator are savable but the rest(poly fuel res, the mounts and lines are shot. The plastic stock fuel lines were cut off by the previous owner. Are you suggesting drawing fuel from the cell with a low pressure pump, and connect that to the stock setup just as the factory tank was and use new factory fuel lines? Thanks

Bildon
02-15-2001, 11:02 AM
Yes, Junk yards are an IT racer's best friend http://Forums.ImprovedTouring.com/it/biggrin.gif

You are confusing me a bit with your descriptions however. You should have:
A) Fuel Tank (Polyethylene)
B) Low pressure pump (inside tank's access panel)
C) Surge Tank (black plastic box with
D) High pressure pump inside it.
E) Plastic and rubber lines to front.

Is this your current setup? Are the tank mounts or the Surge tank/pump mounts shot?

- Bill

MikeM
02-15-2001, 12:01 PM
Bill, I have:
A) Fuel Tank (Polyethylene)
Tank is disconnected, soon to be removed.

B) Low pressure pump (inside tank's access panel)
Still in the tank.

C) Surge Tank (black plastic box with
mounts broken.

D) High pressure pump inside it.
Can be reused.

E) Plastic and rubber lines to front.
lines damaged and not usable.

F) small can connected in between fuel pump and fuel filter(accumulator?) looks reusable.

Additional Stuff:
15 gal sportsman fuel safe mounted in a steel can on rear seat floor. Fuel Safe optional surge tank(in cell) with one way valves to trap fuel. Two 6AN fittings on cell one feeding from fuel safe "surge tank" and the other for return.

I was told that with this "surge tank" in the cell that I could run a High pressure pump directly from the cell without pickup problems, although I don't think the source had ever done it on a VW. Thanks




[This message has been edited by MikeM (edited February 15, 2001).]

Bildon
02-15-2001, 12:16 PM
Mike, that "small can" is your filter. Replace it. You can loose a lot of pressure there.

The surge tank with HP pump can be tie wrapped up to the old mounts. Mine is.
http://Forums.ImprovedTouring.com/it/biggrin.gif

Now about the race cell....
15 gal!? You racin' to china? http://Forums.ImprovedTouring.com/it/biggrin.gif

To do it right you really want a LP and HP pumps. In fact you want 2 of both switched separately for redundency.

Email me and I'll send you a diagram and pictures of how to do it right.

PS - On a Golf I'd still stick with the stock tank. They really are maintenence free and will not starve for fuel at all until the tank is bone dry. My .02

- Bill

Bildon
02-15-2001, 12:19 PM
Weird, my email isn't displaying here: [email protected]



------------------
Bill Sulouff - Bildon Motorsport
Volkswagen Racing Equipment
www.bildon.com (http://www.bildon.com)
http://www.bildon.com/images/bildon_a3_sm.gif

Bill Miller
02-15-2001, 01:58 PM
Hey Bill (Bildon), do you know if an A3 GTI has the same LP/HP setup in the tank? We've parted out a '95 GTI VR6, and are just getting ready to junk the shell. It still has the gas tank in it. I never even thought about looking there for the stuff.

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MARRS #25 ITB Rabbit GTI

John Herman
02-16-2001, 08:25 AM
Where is the surge tank located on the GTI's. This seems like it might fix a problem of mine. What kind of pressure and volume does the HP pump put out?

racerjake
03-24-2001, 05:18 PM
I currently have a car with a fuel cell. Two low pressure pumps and one high pressure pump which feeds from a reservoir. I was having problems at Road Atlanta which I thought were electrical but I have just found that the low pressure pumps are failing. They are faucet pumps which I was told after the fact they were not my best choice for pumps. WHich low pressure pumps should I put on the car. Internal or external is fine with me. If I go with internal will I need to make any modifications to the cell?

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racerjake

Ryan Williams
03-25-2001, 02:44 AM
I use an external Carter low pressure, and it seems to work well. For more details, please read my previous post in this series.

Mark LaBarre
03-25-2001, 10:22 AM
I've talked to denver recently, and the resevoir or external surge tank is not provided for in the rules. I suppose if it was FIA rated it could be called a fuel cell, but then you would have 2. This was not good as I was just about to do that very thing when I install my cell.
Mark

racerjake
03-25-2001, 11:00 AM
Ryan,
DO you know the specifics on the pump? MOdel # size and fuel flow. Currently I have two low pressure pumps(that are failing at the same time) and since I have a race this coming weekend I need to get this done. I wish I would of discovered what the real problem was earlier.
Thanks

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racerjake

Ryan Williams
03-25-2001, 03:55 PM
I don't have the literature on the Carter pump here at the house, it must be at the shop. However, the Carter low pressure pump has a pressure rating of 5 to 6 psi and is normually used on carb applications such as big block ford and chevy. The pump will accept pipe thread AN fittings, and I installed AN lines throughout the primary fuel system. If the pressure is too much for your application, you can install an adjustable fuel pressure regulator. In my GP Wabbit production application, I use the Carter to feed a reservior that subsequently feeds the VW CIS high pressure pump. The reservior has an overflow line back to the fuel cell so I am not concerned about the pressure and output of the pump, as the reservior is always full. To protect the Carter pump, I installed a Fram fuel filter prior to the pump. I probably will not get to the shop until next Tuesday if you really need the details. Sorry I don't have the pump specs at the house. Another source of information is Walt Puckett ([email protected]) who has a race prep shop and races VWs. Tell Walt that I referred you to him. Regards, Ryan.

[This message has been edited by Ryan Williams (edited March 25, 2001).]

Bill Miller
03-25-2001, 04:57 PM
Mark,

That's interesting re: the surge tank and the rules. I know several people that run these, and I was going to put one in my car. I guess I should find out about the legaility first.

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MARRS #25 ITB Rabbit GTI

Bildon
03-25-2001, 05:26 PM
Yup, this "discussion with Denver" is alarming. Yet again, a gray area in the rules?

The way I read it, the ITCS defers to the GCR section 17.12 for cells. It mentions that multiple cells are legal. So you can call ONE cell a main cell and the other a SECONDARY cell (surge tank) Gotcha Denver! http://Forums.ImprovedTouring.com/it/biggrin.gif

I've never seen a protest for fuel systems as long as all pumps, tanks, etc are either in the cell or inside the box surrounding the cell.

Anyway a separate Cell / Surge system is standard on many VWs to start with.



------------------
Bill Sulouff - Bildon Motorsport
Volkswagen Racing Equipment
www.bildon.com (http://www.bildon.com)
http://www.bildon.com/images/bildon_a3_sm.gif

racerjake
03-25-2001, 09:13 PM
If I am understanding this correctly you are running only one low pressure pump. Is it hooked to both pickups or do you have just one pickup in the cell? Also do you have two inlets into the surge tank or just one?
I currently have two pickups and two low pressure pumps with two inlets into the surge tank. I am asking a lot of questions because I am trying to get it right this time so I dont have to play with it later.
Thanks

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racerjake

Ryan Williams
03-25-2001, 10:03 PM
In regard to your question, my cell (Failsafe)has only one pickup tube. From the fuel cell, I have an aeroquip AN#06 connected to the input of the Fram fuel filter, from the Fram with another AN#06 to the low pressure Carter pump, from the Carter with another AN#06 to the input of the reservior. Besides the fuel input on the top of the reservior, the CIS "fuel return" AN#04 terminates into the reservior, and lastly a reservior "overflow line" AN#06 goes back to the fuel cell. The Carter pump is about twice the size of the pump that you are currently using on your car. From my experience with Carter pumps, they last a long time.

Question for you: Do you have a reservior "overflow line" back to your fuel cell? I may be wrong but it is possible that your two small electric pumps are supplying more fuel than the CIS pump will flow, and thus the two pumps are "deadheading" which may cause premature failure. The purpose of the "overflow line" is to prevent an accumulation of pressure in the reservior, and the CIS pump thinks it is taking fuel as if the fuel was coming from the factory tank. The "overflow line" also prevents a "deadheading" effect on the low pressure pump, hopefully extenting the life of the pump. At least this is my theory but we all have theories! Ha! If I get to the shop on Tuesday, I will look for the specs on the Carter pump. If you want more information, please email me at [email protected] Regards, Ryan.

racerdrew43
12-24-2001, 04:21 PM
Ryan,
I dug up this older topic. I'm getting ready to plumb the new fuel cell for 80 scirocco.
what type of resevoir tank did you use(brand,model, size, home made???) and how did you vent the tank?
I've heard of other ways to do this but your way is the way that makes the most sense to me. The new cell has onlt two pick up points, which means I can use 1 for a supply to the filter/low pressure pump and use one for the return/equalizer from the sump, but then I'm short 1 breather. Thanks Ryan, Drew

Ryan Williams
12-24-2001, 05:46 PM
Drew, I fabricated an aluminum reservior that holds about a quart of fuel. I found the aluminum cylinder that was too long, so I cut the cylinder so the remaining portion had a volume of about one quart. Next I took a piece of aluminum (1/2 inch thick) and made a circular top that was TIG-welded to the cylinder. The top was then drilled and tapped for AN fittings, plus one pipe fitting on the bottom.

One of the top fittings is the supply line from the main fuel cell, the other fitting is the CIS return line, and the last fitting is an overflow "return" line to the fuel cell. Since my Carter Low Pressure pump probably keeps the aluminum reservior full, the overflow line basically vents and returns an excessive fuel to the fuel cell.
The bottom fitting on the reservior feeds the input of CIS High Pressure pump.

The entire fuel cell is vented at the lid of the fuel cell. I ran 9 races during the 2001 season, and I never had any fuel problems. If you want a diagram of my fuel system, please send your US mailing address to [email protected], and I will drop a copy in the mail for you. Happy Holidays, Ryan.

racer14itc
12-24-2001, 09:31 PM
Originally posted by Mark LaBarre:
I've talked to denver recently, and the resevoir or external surge tank is not provided for in the rules. I suppose if it was FIA rated it could be called a fuel cell, but then you would have 2. This was not good as I was just about to do that very thing when I install my cell.
Mark

Walt's surge tank is in actuality a "fuel filter" as it has a filtering element built into it. It's about the size of a coffee can, and coincidentally holds about a quart. It's used in the same setup as Ryan describes, with one Carter low pressure pump feeding it, and two outlets: one to the CIS pump and the other returns back to the tank. It's pretty simple.

In my ITC car, I have a fabricated aluminum surge tank that is internal to the tank, which is part of the fuel cell as far as I'm concerned. It uses a Carter pump to pickup fuel from the tank, and pumps it directly into the surge tank (through one of the many fittings on the filler plate!). The fuel return line also feeds into the surge tank. The CIS pump feeds off the surge tank. The fuel cell looks like a alien life support system with all of the hoses connected to it: two for the low press pump, one for the high press pump, one for the return, and one for the vent! And the surge tank has the capability for dual low pressure pumps to feed it.

Hoping to avoid all of the this, on my GP car, I purchased the optional in-cell surge tank that Mike M describes. It has three check valves built into it to allow fuel in under cornering and braking and has a single outlet for the fuel pump. Since I mounted the CIS fuel pump nice and low, I'm hoping that it'll work fine once it establishes a siphon effect. We'll see. My fuel cell is also 15 gal, but it was "free" so I decided to keep it!

I've also had the Facet solid state pumps fail on me, and found that they also need to be mounted lower than the cell to work well. In addition, their capacity is pretty meek and can't keep up with the fuel flow needed by the CIS. Once I switched to the Carter pump, all problems disappeared. Noisy bugger though. http://Forums.ImprovedTouring.com/it/frown.gif

Mark

#14 ITC VW Scirocco
#14 GP VW Scirocco

racerdrew43
12-25-2001, 11:03 AM
Ryan and Mark,
Thanks for the help - Merry Christmas.
Drew