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The symptoms indicate pump cavitation. Cavitation is obviously bad, but can also damage the pump. Cavitation is caused by pump intake restriction of any type. Restricted filters, pickup socks, pickup diameter, fitting restrictions, lift head (height), etc.
Those pumps suck at sucking.
The pump feed circuit is commonly tested by gravity flow-testing for pump flow rating, ensuring no restriction. This is difficult, and Ford used a low-pressure in-tank pump to feed that same Bosch-type HP pump for many years and models, as their choice of solution. They also used a fuel surge tank (accumulator) to ensure the HP pump never ingested air, thereby ensuring the injectors always received full pressure without bubbles, to the bottom of the tank. With their solution, no tank mods, baffles or sumps are required. You may consider one or both of these options.
Here is a diagram I made to depict the general features of the Ford system and similar conversion options, also used by many other OEMs and a favorite in racing for positive fuel feed:
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Those pumps suck at sucking.
The pump feed circuit is commonly tested by gravity flow-testing for pump flow rating, ensuring no restriction. This is difficult, and Ford used a low-pressure in-tank pump to feed that same Bosch-type HP pump for many years and models, as their choice of solution. They also used a fuel surge tank (accumulator) to ensure the HP pump never ingested air, thereby ensuring the injectors always received full pressure without bubbles, to the bottom of the tank. With their solution, no tank mods, baffles or sumps are required. You may consider one or both of these options.Here is a diagram I made to depict the general features of the Ford system and similar conversion options, also used by many other OEMs and a favorite in racing for positive fuel feed:
