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Engine Fuel pickup problems

  • Thread starter Thread starter 93CalypsoConvert
  • Start date Start date Apr 5, 2023
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    fuel gas tank
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from6to8

There's suction so I used that end O_O
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#21
  • Dec 10, 2025
  • #21
Noobz347 said:
The 255L HP pump is the only pump you need. The T-Rex is [not] for you. It designed to supply the pressures necessary from the volume fed from the stock 88LPH fuel pump to an FMU.

The T-Rex will be a restriction with the 255L HP.

The Boost-A-Pump is nothing more than a voltage regulator. You can adjust fuel volume from the in-tank pump and keep it at a saturated and regulated voltage (no spikes or drop-off).
Click to expand...
yeah i forgot that the complete kit comes with an fmu which I won't need to run anyway and I got the tuner kit not the complete kit. It looks like the gss340 255 is a high pressure so not sure why Vortech told me earlier the gss392 is equivalent to the t rex that comes with the kit. So yes looks like I should be fine then .......

https://lmr.com/item/LRS-9350D-K/1986-97-Mustang-Walbro-255-Lhp-High-Pressure-Fuel-Pump-Kit?utm_source=google&utm_medium=cpc&gad_source=1&gad_campaignid=20122150522&gbraid=0AAAAAD62FUxkc7olHzrFb5bn-uKa4JEQN&gclid=EAIaIQobChMIvPW80bS0kQMVmltHAR3sdjXuEAQYASABEgKSzPD_BwE
 

2000xp8

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#22
  • Dec 11, 2025
  • #22
Just run the gss340.
I didn't think the boost a pump was ever a thing for cars with return systems, i was under the impression that is how you increased pressure for non return systems. Foxes just dump the excess back in the tank.

I've run external pumps, it's expensive and a pain to setup.
With that advent of the aeromotive in tank kits (i run the 340lph kit), i would think that other than the most extreme setups, the vast majority no longer have pumps outside the tank.
 
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from6to8

There's suction so I used that end O_O
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Sep 2, 2012
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#23
  • Dec 11, 2025
  • #23
2000xp8 said:
Just run the gss340.
I didn't think the boost a pump was ever a thing for cars with return systems, i was under the impression that is how you increased pressure for non return systems. Foxes just dump the excess back in the tank.

I've run external pumps, it's expensive and a pain to setup.
With that advent of the aeromotive in tank kits (i run the 340lph kit), i would think that other than the most extreme setups, the vast majority no longer have pumps outside the tank.
Click to expand...
Yes that's what I'm gonna do
 

AeroCoupe

lube between the nut and the face. I know my lubes
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#24
  • Dec 11, 2025
  • #24
The boost-a-pump has nothing to do with returnless or return systems.

https://kennebell.net/wp-content/uploads/2022/03/Kenne-Bell-Boost-A-Pump-Theory-Explained.pdf
 
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Noobz347

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#25
  • Dec 11, 2025
  • #25
The Boost-A-Pump can boost volume (an increase in voltage makes it pump faster). Pressure is a limitation of the pump's internal bypass and/or regulator in a return-style system.

Historically, Walbro 190L pumps had an internal pop-off of around 60 psi. Back in the day, you wanted to avoid these pumps for anything running an FMU. So, many just went straight to the 255L HP to avoid the issue altogether.
 
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