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Fuel setup - Main fuel ms & dutycycle.

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-In what way Main Fuel ms affects injector duty cycle ?

-Currently i am seeing 73 % duty cycle @ 1.34 BAR with main fuel ms set at 6ms .

base fuel pressure set @ 43 Psi ,FIC 1100 high z injectors. Walbro 255 LPH, 93 Octane.

Do you think this walbro is not upto the task ?

Please advise.

First of all, what ECU are you referring to?

In an injection time based ECU, the fuel main value doesn't specifically define the injector duty cycle. Instead it is used to achieve good resolution in the main fuel table. Watch this webinar which explains the relationship - https://www.hpacademy.com/previous-webinars/fuel-table-resolution/

To find out if your fuel pump is capable of supporting the required flow, you need to monitor fuel pressure under high load. If you're using a normal vac referenced fuel pressure regulator, the fuel pressure should rise in a linear way with boost. For example if you're running 3 bar base fuel pressure and 1 bar boost pressure, your fuel pressure should be 4 bar. When you're getting to the limit of the fuel pump, you'll see the fuel pressure drop at high load and high rpm.

I am using Link G4+ TOYOTA 3SGTE -

You are right Andrey. So Basically what you are saying is that Main Fuel ms will not affect injector duty cycle any how whether i increase it or decrease it.

How can i log the fuel pressure ? can i wire the signal and voltage wires from fuel pressure sensor

to the ECU instead of fuel pressure gauge ? I have seen Fuel pressure defined in one of the inputs.

- I am using the rising rate FPR .. I feel that the fuel pump isnt upto the task and i might need to replace it .

- Today i tested the car again and at 1.5 BAR the injectors got maxed out... Ill try Aeromotive 340 LPH pump.

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