EFI Anyone?

[Luce]

What I did on the wife's c3 that worked great was kept the original (not factory, but...) mechanical fuel pump and added a surge tank where behind the drivers wheel well. Put a walbro under to feed efi, regulator return goes back to surge tank. Then the excess volume from the surge tank goes back to the tank via the old vent line. Without a float, the mechanical pump keeps fresh cool fuel in the surge tank, full to within 1/2 of top giving 1.5 gallons or so reserve if the mechanical sucks air. So I didn't have to mess with the original tank.

Also, there's a filter between mechanical pump and surge tank to keep debris from original tank out of the surge tank.

In my cobra, the surge tank is inside the main tank, kept full by venturi pump fed by return. Also has trap doors keeping fuel in middle section of tank. Never had any starvation.

Get it in and tuned and you'll love it.

[spdbrake]

If I eventually go to a in-tank pump for my FiTech EFI I will def add a Holley Hydramat to the pump Pick up.
https://www.holley.com/products/fuel_systems/hydramat/

[Tom Wells]

RalleySnake,

I have one of these feeding the 557 in my Mercury Zephyr station wagon: https://www.summitracing.com/parts/aei-18688

It is installed in the stock Mercury wagon tank following Aeromotive's instructions.

I run the car on the highway, in town, and also do track days at Daytona on the Rolex 24 Hour course with it. Highly recommended. Easy install as long as you have a tall enough tank, and can remove/replace the tank without too much hassle.

On the other hand, I have a drag racing type sump welded to the bottom of my Cobra's aluminum tank, about 4 or 5 inches deep and six inches or so square. It extends down at the rear of the bottom of the tank, so you can see it if you know to look for it. The pickup is under the sump, a fitting installed as a drain so to speak at the bottom of the sump; there are circular holes in baffles above the sump to further contain gasoline. I use an external Aeromotive A1000 pump located in front of the tank.

Both setups use 100 micron filters in front of the pumps, and 10 micron filters just before the injectors.

These obviously are not the only two ways of doing this job; they do seem to work. Each has run 10s of thousands of miles with only one A1000 pump failure. They each seem to work fine on the street and on the track.

Before I did the tank mod for the Cobra, it would run out of gas during a 75mph turn on the Interstate. Now it is fine!

Hope this is of some help,

Tom

[RallySnake]

You guys are a wealth of knowledge, thank you very much!

Joyridin', I would really like to see a diagram of your baffles. Since I read your reply, I have been studying tank baffles and have learned that there are wrong ways to do it. The blocks for O2 sensors sounds like a lot of work. But, putting the sensor out on the side pipe collector would not look good. I have been running an A/F gauge with an O2 sensor on the pipe for #3 cylinder and it gives pretty stable readings. Do you think that will be good enough for the Holley system?

Luce, How did you get a surge tank inside the main tank? The venturi pump is a second electric fuel pump? Please tell me more.

spdbrake, The Hydramat gets raves from off-roaders and it is my backup plan, too. It is just SO expensive!

Tom, I considered putting a sump in my tank. But, I have track rods for the suspension running under there. The Aeromotive system is beautiful, but twice the price of the tanks.inc PA-4 system. There is no way to add a second pump to that one. It is interesting that even the high dollar Aeromotive pump can fail. That's why I feel strongly about having a second pump. Last time it failed (when I had only 1 pump) was in East Los Angeles. Not a great neighborhood to be waiting for a tow truck!

[Cracker]

I had Fuel Safe build me a new cell this last Fall...I run a swirl pot but was a little concerned about the pick-up in the cell. I opted to have them install a Hydromat but later found out they can cause issues with overheating the pump. Now, I wish I hadn't added it - just a thought.

Cracker

[spdbrake]

Originally Posted by Cracker

I had Fuel Safe build me a new cell this last Fall...I run a swirl pot but was a little concerned about the pick-up in the cell. I opted to have them install a Hydromat but later found out they can cause issues with overheating the pump. Now, I wish I hadn't added it - just a thought.

Cracker

Thanks for the info Cracker. Can you link the pump heating issues you found please. I've spent a bit over an hour now on Google doing various searches and Nada thus far. Thanks.

[Luce]

[quote=RallySnake;1436479]You guys are a wealth of knowledge, thank you very much!



Luce, How did you get a surge tank inside the main tank? The venturi pump is a second electric fuel pump? Please tell me more.




I made my own tank, 16 and 18ga 304 stainless, and it included a 1 gallon milk jug sized box, 1/2 open on the top.

I got the idea from my 88 ramcharger.

Where the return line comes back to the tank, it's pinched down to 1/16" nozzle. It provides 30 psi backpressure when the pump is running full speed (and the engine is using zero of the fuel) so it doesn't interfere with the regulator. Than nozzle is at the bottom of the tank, and it squirts into a 1" tube that enters the box. The velocity of the fuel out of the return drags gallons of fuel per minute into the box, keeping it full at all times.

Found a pic. I tested it in the swimming pool with an old fuel pump pumping pool water. You wouldn't believe how much fluid the nozzle drags in. I would say better than 1200 gal/hr. It could fill in under 3 seconds. The flat bottom sits and is welded into bottom of the mail tank. I also added a skirt around the cutout so it would suck the last 1/2" of fuel from the main tank.