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Discussion Starter · #1 ·
I am planning on putting fuel injection in my maverick. The problem I have is where to mount the inline high pressure pump. The installation instructions say the the pump must be mounted no higher than the lowest point on the tank. I am guessing this is because the pump does not provide much suction. The recommended location does not really seem to exist on my car because the tank sits quite low. My question is where do most people who do this conversion mount the pump? I read the tech articles on FM where they mounted the pump above the tank. However, I looked up the pump they were using and it has the same mounting requirements as the one I was looking into. Also, they were having what appears to be fuel starvation problems at 3500RPM. It might be due to the pump mounting location. Any thoughts? I looked up what ford did in the late 80's when they used an inline fuel pump for the CFI systems. It turns out they used a low pressure in tank pump in addition to the high pressure inline (or chassis mounted as they call it) pump. However, Holley does not recommend this. They claim it will also lead to fuel starvation. The system I am looking to use is the Holley TBI system with the commander 950 control box. Thanks for your time.
 

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The Three R's Of Fuel Delivery-

Do not mount an EFI electric fuel pump so it has to draw fuel from the tank. This creates a negative pressure in the fuel line allowing the fuel to boil at a lower temperature.

The pump must be mounted in the tank or in a location so that it is gravity fed.

Fuel should be pushed through the fuel filter. Pulling fuel through a filter can cause cavitation.
 

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Hi there,

We actually discussed the mounting with the manufacturer Walbro. They told us that their inline pumps do not have to be mounted below fuel level. They will suck up fuel just fine. However, there is of course a natural limitation to this. You'll be fine if the pump is 6-12" above the pick up point.

On our Project 67 "DIY EFI" we actually have not moved the pump location from where we showed you in the article. Our 3500 rpm problem turned out to be ignition related (see the part III). The engine made 363 horsepower at the wheels with no fuel issues.
 

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Discussion Starter · #5 ·
Outstanding! This is good news. So I guess the key here is for me to call Holley and make sure the same is true for their pump. Worst case then would be that I could switch to the pump you guys used in your build up. Thanks for your time guys. I will probably have more questions along the way. By the way, I was having trouble finding part III. Has this part been published yet?
 
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