Project Fuel Tank

[Luce]

Since this is inside the cabin of the car I would not rely on any fitting other that hard metal pipe. This means external fuel pump. It adds complexity and requires space, but a surge tank and jockey pump would be a nice addition. Fuel starvation with an EFI pump is a real problem. You lose fuel pressure and pump prime and the engine is dead until prime and pressure are regained, then you'll likely have a hiccup when the bubble makes it to the injectors.

[C5GTO]

Originally Posted by Luce

Since this is inside the cabin of the car I would not rely on any fitting other that hard metal pipe. This means external fuel pump. It adds complexity and requires space, but a surge tank and jockey pump would be a nice addition. Fuel starvation with an EFI pump is a real problem. You lose fuel pressure and pump prime and the engine is dead until prime and pressure are regained, then you'll likely have a hiccup when the bubble makes it to the injectors.

Thanks for the reply and sorry I gave a misleading description on the tank location. It is not actually inside the cabin. It does run between the seats but the car has a "high backbone" aluminum chassis that covers the fuel tank. So there's 1/4" aluminum sheet between the fuel tank and the cabin. There is no exposure between the tank and cabin.



I'm very familiar with EFI, fuel sloshing and then fuel starvation. I had that issue in my Cobra for a long time before finally finding a solution for it. This is why I'd like to find a in-tank pump solution for the Miura.

Does the additional information change your answer?

[Gaz64]

With a tank mounted up inside the tunnel like that, I would run an external pump.
If there is ever a pump problem, way less work to repair.
I don't see having an access panel from the top side will be roadworthy, with a module internal pump.
You certainly can't mount a pump assembly like that lower than fuel level, as in your case with a third of the volume above the pump.

[Shootnride]

Joel,

Although I am very impressed with your build, I don't have any input to offer beyond what has already been said. But, I am very curious about the piece of blue machinery sitting next to the car. Can you enlighten me a little.

Thanks

Ted

[C5GTO]

Originally Posted by Shootnride

Joel,

Although I am very impressed with your build, I don't have any input to offer beyond what has already been said. But, I am very curious about the piece of blue machinery sitting next to the car. Can you enlighten me a little.

Thanks

Ted

There's actually 2 blue colored machines there both of which I built. One is an English Wheel. The other is an Air Power Hammer.



The power hammer is my goto machine for metal shaping operations. It uses tooling from TM Technologies -Kent White who you might recognize as a metal shaping guru. The power hammer shrinks, stretches, and more. It and the English Wheel will get lots of use while I'm making the aluminum body for the Miura.

Miura build diary here: Modern-day Miura

[Tom Wells]

C5GTO,

I have the Aeromotive 340 in-tank unit in my 1981 Mercury Zephyr wagon. I went for the larger pump because it has a 557.

The wagon has more than 15K street and track miles without any hiccups. And I am familiar with EFI fuel problems caused by uncovering the pickup.

The 24 hour Rolex course at Daytona did not cause any problems during the four track days I ran there last year.

The Cobra is another, older, story. The Aeromotive setups were not around 15 years ago or it would have one also. Starvation occurred in that car even on an interstate when negotiating curves at legal speeds.

The answer to that one was to construct a "box" about 8" on a side below the floor of the tank, putting a piece of perforated aluminum at its top. The pickup is located near the bottom of the box. It was the result of an old drag racer's trick of putting the pickup at the bottom rear of the tank; this box kinda moved that idea to a 3-D version. The pump itself is external.

The "box" has been run 38K miles on the street and many, many track days including Sebring and Daytona among others and nary a burp.

HTH,

Tom

[C5GTO]

Originally Posted by Tom Wells

C5GTO,

I have the Aeromotive 340 in-tank unit in my 1981 Mercury Zephyr wagon. I went for the larger pump because it has a 557.

The wagon has more than 15K street and track miles without any hiccups. And I am familiar with EFI fuel problems caused by uncovering the pickup.

The 24 hour Rolex course at Daytona did not cause any problems during the four track days I ran there last year.

The Cobra is another, older, story. The Aeromotive setups were not around 15 years ago or it would have one also. Starvation occurred in that car even on an interstate when negotiating curves at legal speeds.

The answer to that one was to construct a "box" about 8" on a side below the floor of the tank, putting a piece of perforated aluminum at its top. The pickup is located near the bottom of the box. It was the result of an old drag racer's trick of putting the pickup at the bottom rear of the tank; this box kinda moved that idea to a 3-D version. The pump itself is external.

The "box" has been run 38K miles on the street and many, many track days including Sebring and Daytona among others and nary a burp.

HTH,

Tom

Hmmm...now you have me thinking

Maybe I can add a shallow sump at the bottom rear of the tank, with a lid that traps the fuel from escaping on braking. It would be filled in low fuel condition by acceleration when the fuel sloshed rearward in the tank. The tank is narrow, about 10 inches wide so cornering shouldn't cause a sloshing issue for fuel in the sump. If the pickup and return lines are both plumbed to the sump then return fuel should also ensure the sump has fuel.

I'll have to fit the tank up into the chassis to check if there will be space for this type sump with all the coolant, heater, and A/C lines running under the tank. Even a 3/4" deep sump might be enough to do the trick.

Tom: in case a sump isn't possible, I have a Aeromotive in-tank pump question for you. Is the top of your in-tank unit always above the fuel level? Or is there fuel sitting against the seal when the tank is full? If the later, have you noticed any leakage at all?

[Tom Wells]

Joel,

If the Aeromotive installation "wept" I wouldn't know: the tank is up against the rear floor within about an inch so I can't lay eyes on it. No gasoline aromas, so maybe that's a good sign.

Here's the PDF for the install: https://www.aeromotiveinc.com/wp-con...8809-0revE.pdf

Maybe you can get some ideas there. It does have a heckuva gasket that I hope is fuel resistant and no aroma of fumes happens in the garage after several years.

My sump for the external pump in the Cobra is about 3" plus/minus deep - memory may not be accurate and the car is in the paint shop (don't ask). The top of the sump is perforated so the gasoline must take a bit of time to exit if it tries.

Each works fine for me in its respective car, so I think it's your choice.

Tom

PS: Here are a few pictures of the Zephyr gas tank install for the Aeromotive pump: Zephyr fuel pump & tank for EFI - FirstCoastCobraClub