Fuel cell install

[Bildon]

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!

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.



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Bill Sulouff - Bildon Motorsport
Volkswagen Racing Equipment
www.bildon.com

[racerjake]

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]

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]

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]

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]

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.

Mark

#14 ITC VW Scirocco
#14 GP VW Scirocco

[racerdrew43]

Ryan and Mark,
Thanks for the help - Merry Christmas.
Drew