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Discussion Starter #1 (Edited)
Fuel Injection Gas Tank internal pump pick-up design

Question on Fuel tank & Internal pump/pick-up design:

I have a 15 Gallon rectangular Aluminum RCI Fuel Cell with rear sump. Car was a Carburetor car, used rear sump and external low Pressure fuel pump. Worked fine for many years, did have some fuel slosh issues when very low tank level.

Converting to Fuel injection. First step was to use an external surge tank with an internal pump, worked OK. System is a FITECH with a modified FCC. Now looking to simplify the system to one High Pressure fuel pump. Will go with an internal pump inside the tank. I can buy a kit that has a small windage area and go with that. Kit is by TANKS INC, PN PA-4

OR, I did purchase a fuel pump sock that is quite large, and about the full width on my tank, and about 4" wide. My thinking was that it could keep "wet" in the fuel no matter the level, and cover any slosh. I am thinking of using this and then no internal baffling. It would locate in the rear half of the tank so always wet under acceleration. Only hiccup would be that the electric pump itself would have to be a little higher than the kit so I can make the plumbing connections.

So, my questions:

1 - which method - Baffle or large sock - would work better in a road racing car?
2 - does the electric pump have to be as low as possible, or can it be raised up an inch or two?

I am very curious to get any and all feedback.
 

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So you need to consider if you are going to possibly run out of fuel at any time during racing. We endurance race, and as such almost always run one of our two tanks completely dry during races. We run fuel injection and two high pressure pumps. That said, the high pressure pumps really do not like running dry and can easily fail if run dry for even short periods of time. It is for this reason that we run a low pressure pump to a common "mixing pot" and then run the high pressure pumps off the mixing pot. We have fuel level sensors in the main tanks to tell us with a light when the tank is empty. These are very accurate and come on within a lap of the tank being empty. We run a pickup at the rear of the main tanks, and the low pressure pumps are self priming so if they suck air it is not an issue. This system has served us well for over ten years of racing and while we replace pumps every couple of years as a maintenance item, we have had no failures. You can think of the "mixing pot" as a "shock absorber" for the high pressure pumps so they don't ever run dry. This method, as it sounds like you are currently running about the same setup, is equally applicable to a single feed system. IMHO this is the most durable setup if you know you are going to run low on fuel and the pumps have a chance of running dry.

I did debate using the in tank high pressure setup, but the complexity of designing the tank to make sure there was little chance of the pumps running dry via a designed into the cell sump just wasn't worth it. Although I have worked on cars with those systems and they have worked fine, they also were not prone to running dry due to trying to get every last drop out of the tank on a regular basis. If that is the game you are playing, then I would recommend you staying with the setup you have.
 

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FWIW,
I run a stock mounted fuel pump (255LPH) in a stock tank. I run a Holley EFI and have never run out of fuel or had issues while doing track days. The car will tend to get butt light when below half tank, but that's not a fuel issue, it's inertia taking over, so I just drive different. Though about a Holley fuel sock, but haven't gone that route just yet. Also, this is a mainly street car that sees about 8-10 track days a year.

I think either of your ideas would be fine. The Holley sock sounds neat, but it is $$$. If you can get a baffled tank, it may be better, but a fuel cell for track use only would be best. imo.
 

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we tryed the sock in the cell on jg's cobra and it did not work at all.
woked with holley.
tryed everything they recomended still no luck.
thank goodness they let john return it.

We ended up with dual pumps in the cell to a common line feeding the EFI.
works awesome

on wayne P's roadster we went to a radium system
it has worked flawlessly since day 1 .
single intank pump feeding a intank surge pot.
in the surge pot is another pump feeding the carb.
 

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1 - which method - Baffle or large sock - would work better in a road racing car?
I am very curious to get any and all feedback.
By "large sock", do you mean the Holley Hydromat? If so, I would try that first.
 

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Discussion Starter #6
Been a while since on this thread.

So, an update:

Did use a Hydramat. So far, one HPDE, ran without a miss.

From a thread run on tjhe roadster section:

Fuel tank pick-up - This is where I varied a little, due to the fact I tun track alot. I got a pick-up assembly for my tank from Tanks Inc. But I modified mine to accept a Holley Hydramat, rather than an internal pump. The mat runs the full width of my fuel tank, so fuel slosh is not a problem. Worked great, just make sure you install it properly, and at the correct depth for best results.

Fuel Lines - Definitely go all new, proper diameter and fittings, pressure line to the throttle body, return line back to the tank. No breaks, just a one-piece properly sized line.

Fuel pump - two schools, both work. I used a Walbro 255LpH external only due to the design of my fuel cell. Run a relay that is triggered by the ignition swith, heavy gauge wire, and 20A fuse. DO NOT USE the fuel pump control from the FITECH (Orange Wire). Let it run at full, and let the regulator and return line take care of extra fuel.
 
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