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1965 Ford Falcon Futura
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I,m sorry to see your having problems with the sniper EFI. I installed mine and have nothing but great results.Keep working at it . I installed a IDIDIT steering column in my car and have had nothing but problems . The biggest problem is me. I'm not very good at wiring.The column is very nice ,but the wire loom in my car has been cut up and changed in the past . Now it's follow each wire down. Very few of the wires have the correct colors.
 

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Pull the outgoing line from the pump, stick a fuel line on it and run the pump....should have lots of volume and 28 psi????
 

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1962 Ranchero 200 inline, 5 speed
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97 Posts
Discussion Starter · #43 ·
I received a new fuel pump and it was a bit better but still not right. I had installed a new fuel sender and figured maybe there was a restriction somewhere. I ran a fuel line from a gas can to the supply side at the rear, only eliminating the sender and tank. I immediately had full pressure. I pulled sender and the filter at the end of it. I ended up testing the sender out of tank in gas can, with and without filter on the pickup. In the end it’s unclear where the issue was. I’m wondering if the pickup filter was pushed on too far and bottomed restricting flow. It’s plastic with a bottom. In any event, with the wiring pulled apart, pink supply wire directly to battery and fuel it runs and idles. Next step will be to reassemble and clean up engine bay. I am pleased. I have not driven it yet as the wiring is a bit ugly and not secure. I just started a 10 day work stretch so it will sit as is for a while.
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@65ragtopDirk, please pardon the large injection into your thread. I'm adding this here hoping it may be helpful for both you and others that will read your awesome(y) thread in the future. I have extensive EFI conversion experience, and have found some things that are often helpful along the way.

As a rule-of-thumb, if the pump is noisy, you have cavitation (bad). With it pumping fuel, you should feel it humming, and noise should be an electric motor quietly running. How loud? That's hard to describe, but if it's mounted under the vehicle, standing next to the vehicle the pump running (engine off) should be barely perceptible.

If you have louder noise (whining, screeching, buzzing, "vacuum cleaner", etc), then you likely have a restriction. The restriction can commonly be an under-sized feed line, excessively tight-mesh filter, restriction in cheap fittings, etc. Restrictions cause cavitation (bubbles formed by inlet vacuum) that can be very damaging to the pump, and of course reduce or stop fuel flow and pressure, and cause pump and fuel overheating.

Suggestion—look at the issue from both "'ends", as running an over-sized pump (pump oversized for the rest of the fuel system or engine) is just as commonly the issue as running a reasonable pump size but with restrictions. Here is a snip of a piece I wrote on fuel pump sizing that not only helps in pump selection, but also analyzing issues, and proving the fuel system is up to the task on a particular project. The piece was written for a 120hp turbo VW beetle as an example:

PSIG said:
Cool. With numbers to work with; rather than just suggest something, I can show you the math and let you decide. I suggest a much smaller pump that will feed 120 to 150+hp, of perhaps 65, maybe up to 75lph max.
:shock:
Now, here's the math to show why and so you don't rapidly overheat your fuel and cause other unnecessary issues.
:ugeek:
How much fuel (straight standard pump gasoline/petrol) does your engine need?:

HP * BSFC ÷ Pounds per Gallon * liters per Gallon * restrictive flow compensation = Design flow in liters per hour at specified pressure and voltage. Whew.

So that's your HorsePower, multiplied by your Brake Specific Fuel Consumption (= pounds per hour fuel burned), some math to convert pounds to gallons to liters, and a fudge-factor of 20% to allow for under-voltage, plumbing restrictions, dirty filters, etc. So, you math looks like this:

120 * 0.6 / 6.6 * 3.785 * 1.2 = 49.6 lph

So, a 255 lph pump—actually flowing 255 lph—will feed over 700hp in a well-designed and properly-tuned system. If you do that math, you'll see the [±50lph] results above are about right for only 120hp.
;)


Now you're wondering how I got 0.6 BSFC and 20% compensation, and it still doesn't hit the 65 lph number. Well, most street engines burn roughly 0.5 pounds of fuel per hour, per HP. You are turbocharging an air-cooled flat-4 VW that can typically sustain about 90hp of heat, and will probably try to run it extra rich to keep the poor heads cool while also pushing it for much longer than a typical quick drag run of 10-15 seconds. That will push your BSFC up substantially, and 20% more fuel (dripping rich) is 0.6 BSFC. Next, the 20% buffer (*1.2) was already outlined, and gives more than enough safety factor for long-term wear and other issues—but again test the flow once installed to be sure! I added yet another ~25% just so you are happy it will handle over 150hp.
;)
There's your 65 lph. I had to say 75 lph max just because I can't bring myself to let things go totally out of control. I would rather say 65 max actual.

More than the 50 lph you actually need is wasted in the form of fuel heating like a 100 watt heater in your surge tank.
Image
It also over-taxes the fuel feed lines quicker (assuming a return) and can also over-run the regulator's ability to handle it, causing over-pressure in the fuel rails, especially at lower power levels. To do it right, you will need a large feed line with a low-restriction filter sock that can flow more than your pump's output (test it!). You should have the regulator return to the tank to circulate fuel for cooling. An additional air line from the surge tank to the main (or to a filter or canister above the main) to bleed air bubbles before they get to the pump. 3 surge tank lines. Circulation cooling. Drive happy.
BTW, the fuel system test to verify you have sufficient flow is to run the system KOEO (key ON engine OFF) while (carefully!) flowing the return line into a measured fuel jug for a specific number of seconds. That flow is regulated flow, all of which is available to the injectors, or returned if not used. Run some simple math to see if the return flow equals or exceeds the flow volume the engine needs (above) at max load. Test done! 😎
 

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1962 Ranchero 200 inline, 5 speed
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97 Posts
Discussion Starter · #48 ·
@65ragtopDirk, please pardon the large injection into your thread. I'm adding this here hoping it may be helpful for both you and others that will read your awesome(y) thread in the future. I have extensive EFI conversion experience, and have found some things that are often helpful along the way.

As a rule-of-thumb, if the pump is noisy, you have cavitation (bad). With it pumping fuel, you should feel it humming, and noise should be an electric motor quietly running. How loud? That's hard to describe, but if it's mounted under the vehicle, standing next to the vehicle the pump running (engine off) should be barely perceptible.

If you have louder noise (whining, screeching, buzzing, "vacuum cleaner", etc), then you likely have a restriction. The restriction can commonly be an under-sized feed line, excessively tight-mesh filter, restriction in cheap fittings, etc. Restrictions cause cavitation (bubbles formed by inlet vacuum) that can be very damaging to the pump, and of course reduce or stop fuel flow and pressure, and cause pump and fuel overheating.

Suggestion—look at the issue from both "'ends", as running an over-sized pump (pump oversized for the rest of the fuel system or engine) is just as commonly the issue as running a reasonable pump size but with restrictions. Here is a snip of a piece I wrote on fuel pump sizing that not only helps in pump selection, but also analyzing issues, and proving the fuel system is up to the task on a particular project. The piece was written for a 120hp turbo VW beetle as an example:



BTW, the fuel system test to verify you have sufficient flow is to run the system KOEO (key ON engine OFF) while (carefully!) flowing the return line into a measured fuel jug for a specific number of seconds. That flow is regulated flow, all of which is available to the injectors, or returned if not used. Run some simple math to see if the return flow equals or exceeds the flow volume the engine needs (above) at max load. Test done! 😎
I believe you are spot on. It was restricted or I was sucking air. Pump was very noisy and after I resolved that issue, like you said, pump was very quiet. I found the volume of fuel going through the system to be significant. When I was running out of fuel can the van emptied very quickly. I absolutely appreciate your input. Valuable for this knucklehead and others that will go in like I did.
 

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1962 Ranchero 200 inline, 5 speed
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97 Posts
Discussion Starter · #50 ·
It seem
Well how does it run? Have you got it running proper ?
it seems it idle quite nicely but the next day I had to start a 10 day work stretch. I work through Wednesday. It still in the air in the side yard with wiring hanging loose. On Thursday I may have a chance to get into it and allow it to move under its own power. I’m looking forward to it for a couple reasons. I have another car in the side yard that has been boxed in for a couple months now I think.
 

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1962 Ranchero 200 inline, 5 speed
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Discussion Starter · #51 ·
It’s running. It starts and idles nicely. Engine is smoother than ever. It’s so nice the rest of the car is letting down the engine. I’d say for anyone who has a nice car this will certainly be a nice addition if you’re experiencing any issues with the carburetor. If I had a nicer car I probably would have wanted to run hard lines front to back to keep it clean and more factory looking under the hood. I’m sure it’s still learning. I had one odd thing occur. I was going down a long hill. Off the gas the whole time and when I came to a stop the engine maintained the downhill rpm. I blipped the throttle and it came right down to a proper idle. It still isn’t fully buttoned up. I’ll redo the wiring looms to clean up the engine bay.
 
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