Fuel tanks

[David]

Basically yes but it's a bit more complicated than that.

Each sensor is polled every clock cycle and the running average over a period of time is taken to be the sensor value.

Each sensor then has a table which translates the sensor value to the actual fuel amount. The total fuel amount is then added and another table maps it to the gauge.

The gauge is then only updated every few seconds. The net effect is that no matter how I throw the car around (once I get to that stage!) the gauge won't wildly fluctuate.

In addition it controls the individual lift pumps (to the swirl pot), alternating between tanks by 'picking' the one with the highest fuel level and shutting down the pump if the tank runs 'dry'.

Plus of course a low warning light.

 

[EGLITOM]

Thanks to all for great information.

I like the idea of one fuel sender, simplifies the electric. My guess is the only way to meter two thanks is to have a switch or two gauges (or a double needle gauge like the ones used in aviation).

My fuel system is return-less EFI and plan to use Aeromotive A1000 Bypass Regulator. Even the system is return-less the regulator puts back certain amount of fuel. Not sure what is the amount. If I use two pumps that would mean buying two pumps, two filters, two check valves and a tee to the regulator . The question would be, where does the return go, what tank? Both maybe? I would need a solenoid valve and run everything through a selector switch or a manual selector valve.
Gets complicated really quick.

I understand the idea of a redundancy in having two of everything, but in my system all comes down to the single regulator anyway.
All the chassis will have similar problems not only RCR. Do you run the pipe through the cabin or not? I don't like the thought of fuel in the cabin but it can be done safety with a bit of planning. The cooling pipes don't make it any easier.

Some of trucks (like Ford F150) with dual tanks have a switch inside cabin to switch between tanks and fuel pumps. System incorporates a selector solenoid valve with feed and return in one body. No connection between tanks. So it's been done by big guys and (I guess) it works more or less reliably. That was one of my choices if I go with dual systems.

Regards,
Renato

If i understand correctly, this would be an EFI fuelsystem without a catch tank ? Not sure if this will work. At least you need an internal catch tank to make sure you have no air coming into the high pressure circuit.

In your case it may be a good idea to connect the tanks. Feed the catch tank with a low pressure high volume pump and let the overflow go back into the main tank( the tank where the pump takes the fuel from). Than run a high pressure pump from the catchtank to the Regulator and from the regulator back to the catch tank.

TOM

 

[EGLITOM]

Bill

yes somehow this is my definition. If one tank/pump/ gets clocked or is not providing any fuel anymore for some reason, i can switch to the other tank and pump ( and would not ruin a quite expensive trackday, for which you could easily finance the second pump and filter)

I still do have two gauges and and i switch when the tanks shows about 25% . Just to make sure the pump always gets enough fuel. I think also the difference in the system is based on the different requirements of a carbed or EFI engine. Don´t perceive my system as complicated. 2 sensors, 2 gauges, 2 switches, 2 pumps, 2 prefilters,2 pastfilters, 2 checkvalves, 1 deadend regulator, all symetrical build and flowing.

And yes i don´t think i´m the only one thinking about two different fuel qualities on board. check Dean Lampes thread on his GT40. Espcially with high CR engines and a map controlled ignition advance, one could run a street (rain) mapping and a high performance mapping and not firing away bloody expensive race fuel driving to the coffee shop, which i still like to do with my car as well.

TOM

 

[Mick Ridley]

Tom,

I will be useing carbs on my car.
Could you please post a diagram of your system

Thanks

Mick

 

[EGLITOM]

Mick

here you go

not a diagramm but it shows all the parts

prefilter Aeromotive 100 micron
Aeromotive pump Aeromotive Street/Strip Fuel Pumps 11213 - SummitRacing.com
postfilter Aeromotive 40 micron
Earls check valve ( flapper style)
Aeromotive regulator Aeromotive Carbureted Adjustable Fuel Pressure Regulators 13205 - SummitRacing.com

Lines are teflon ( no fuel dispersion, no fuel smell) Dash 8 till regulator and Dash 6 to carb.

except the pumps beeing noisy it works great. if i have time i will switch to holley gerorotor pumps http://www.summitracing.com/parts/hly-12-150 already have them at home but not installed yet.

THis setup with the pumps mounted a bit lower ( syphoned) allows the pump beeing in fuel all the time thus not running empty and dry. Therefore suction is always good .

Also the position and orientation of the check valve makes sure that it is always closed by gravity ( not flow only) and therefore can not float. Had no issue so far with fuel beiing pushed to the other tank.

TOM

 

[Mick Ridley]

Hi Tom,

That is very helpfull

Thanks

Mick

 

[Renato]

Tom,

I like how you worked out the details in your fuel system. Thanks for posting pictures, that's more than 5000 words right there. :2thumbsup:

Coyote uses return-less system where the fuel rail gets around 55 PSI and that is it. It's regulated going in to the rail, not sure why they did it that way. Maybe production simplicity.

I'm not planning to use a catch tank. Instead I spoke to Aeromotive engineer and he suggested their new Phantom 340 Stealth Fuel System.
From there to a filter and then to the regulator and back from regulator to the tank. It seems they designed this system for tanks like ours where sloshing is an issue. He (Aeromotive engineer) said there is no need for dividers in the tank. I'll put them in anyway.

Regards,
Renato

 

[EGLITOM]

Hi Renato

That looks more or less like an intank catchtank or sort of catchtanksystem

TOM

 

[Renato]

Tom,

Yes, you are right. It incorporates a small tank and foam to soak up the fuel. Also the return is in to the same area.
I kinda like the simplicity and compactness of the setup.
The question is: will it work as advertised?

Regards,
Renato

 

[Renato]

Tom,

BTW, nice touch with the matching color hose clamps!

Renato

 

[Jayson]

That looks like a really good system Renato, have you been quoted a price for it?

 

[Renato]

Hi Jason,

It's available from many online retailers of Aeromotive products but the cheapest I found was on Sparktec Motorsports for $435. Most other places you'll find for about $500. I'm looking to find some customer feed back.
Are you going EFI?

Regards,
Renato

 

[Jayson]

Hi Renato

That price is alot more reasonable, the few places I found it for sale they wanted $549. Buying 2 units plus getting it across the pond and near 30% tax on the final price would make it pretty expensive . At $435 I'm still interested.

I want to go EFI but may have to wait until I get the car running due to budget.

 

[Renato]

Hi Jayson,

I thinking the same way. That is why I want to connect the two fuel tank and use only one pump. Savings are significant. I'm not building a Le Mans car so I'll be happy with one pump reliability. Just wasn't sure if connecting tanks is doable and it seems it is.

Regards,
Renato

 

[Darrin]

Renato, do you know the diameter of the Aeromotive in-tank Phantom setup?

Here is a photo of what we have to work with size wise. If I knew the width, I could calculate if we have 6" of depth (what they say is the minimum) with some (say 1/4") side clearance.

My guess looking at the their photo it is going to be close and we will need some sort of hose extension to go to the bottom of the tank since it appears the thing is much wider than the 2.5" of width across the bottom we have to work with.

 

[Darrin]

Never mind...they had it in a photo on their site. Looks like the thing needs a 3.25" hole.

So, if we want 1/4" on each side, that gives us 3.75" in diameter. We already have 2.5" of that across the bottom so we need another 1.25".

Doing the math I calculate that we get to a width of 3.75" at a height from the bottom of the tank of almost exactly 1.5".

I'll ask them if this setup should work for us (although I'm still thinking an external pump might be as easy all things considered).

 

[Dylan]

If you think there's a chance this thing could be sucking air every once in a while, it might be easier to go with an external pump that you can get at to replace easily.

 

[Jason Ferraro]

I was watching this thread closely as I need to setup my RCR tanks for a coyote as well. I only want one pump as well. I checked out the aeromotive website and it says that this pump can only be used on a return style system. Is the coyote a return less system and if so that would be a problem would it not?

 

[Randy V]

I was watching this thread closely as I need to setup my RCR tanks for a coyote as well. I only want one pump as well. I checked out the aeromotive website and it says that this pump can only be used on a return style system. Is the coyote a return less system and if so that would be a problem would it not?

Those injectors only know 3 things:

Power
Pressure
Flow

They don't car at all how they get all three.. IE returnless or return style really does not matter much to them..

 

[Jason Ferraro]

Thanks. I pick up my tanks tomorrow and will look at this thread for what to do. I have opted to put RCR external tanks in my car for additional safety. I have no experience in fuelling so please keep posting!