hacked89
Full Access Member
Here is a summary of my recommendations from this thread, the fuel math, and the FSV disassembly, cutaways and measurements.
I'll add it to the first post as well.
1. If your injection pump/engine builder informs you that your build requires more than 30gph then delete the FSV, it's internal supply port is 1/4" and you will encounter fueling instantability.
2. If you require up to 70gph (66 to be exact but we are rounding up) you can stay 3/8" supply with a pump whose fueling curve supports it at the documented pressure. If you require 100gph or more (92 to be exact same rounding up to numbers which correspond to pumps) then you should move to 1/2" supply line because otherwise you will be stacking multiple pumps, require higher end pumps to maintain the pressure to fuel flow curve, and have more pressure to flow instability.
Evidence with notations top right:
Stock fueling at stock lift pump psi aligning with original posts
With a 70gph requirement such as my T04Z build
With 100gph requirement, it's clear why you start having fueling stability issues on 3/8" lines, needing to stack pumps, and incurring challenges of maintaining the pressure needed for the flow requirements.
Finally, check out the significant difference of a 1/2" line maintaining flow requirements at an achievable pressure to flow curve ratio for the electric pump
Remember, you must compare this math to the flow benchmarking of the electric pump in order to choose the appropriate electric pump. In general, the higher the pressure, the more amp draw on the pump, the lower the flow rate.
Here is the Gsl392 flow graph i posted earlier
Sent from my SM-G955U using Tapatalk
I'll add it to the first post as well.
1. If your injection pump/engine builder informs you that your build requires more than 30gph then delete the FSV, it's internal supply port is 1/4" and you will encounter fueling instantability.
2. If you require up to 70gph (66 to be exact but we are rounding up) you can stay 3/8" supply with a pump whose fueling curve supports it at the documented pressure. If you require 100gph or more (92 to be exact same rounding up to numbers which correspond to pumps) then you should move to 1/2" supply line because otherwise you will be stacking multiple pumps, require higher end pumps to maintain the pressure to fuel flow curve, and have more pressure to flow instability.
Evidence with notations top right:
Stock fueling at stock lift pump psi aligning with original posts
You must be registered for see images attach
With a 70gph requirement such as my T04Z build
You must be registered for see images attach
With 100gph requirement, it's clear why you start having fueling stability issues on 3/8" lines, needing to stack pumps, and incurring challenges of maintaining the pressure needed for the flow requirements.
You must be registered for see images attach
Finally, check out the significant difference of a 1/2" line maintaining flow requirements at an achievable pressure to flow curve ratio for the electric pump
You must be registered for see images attach
Remember, you must compare this math to the flow benchmarking of the electric pump in order to choose the appropriate electric pump. In general, the higher the pressure, the more amp draw on the pump, the lower the flow rate.
Here is the Gsl392 flow graph i posted earlier
You must be registered for see images attach
Sent from my SM-G955U using Tapatalk