Fuel Pressure Change/Tuning Issue
#1
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Fuel Pressure Change/Tuning Issue
Okay...so I messed up and didn't verify my fuel pressure at idle before I did my tuning. I have a majority of my tuning exactly the way I want it. Fuel Pressure at idle is at 50psi and I am wanting to change it to 35psi. Is there a calculation I can use to modify the existing table to compensate for the lower pressure?
Idle w/ 1000cc/min injectors at 50psi is running a 11:1 AFR on minimum injector timing.
I am hoping that lowering to 35psi it will get closer to reasonable. Any input is greatly appreciated.
Idle w/ 1000cc/min injectors at 50psi is running a 11:1 AFR on minimum injector timing.
I am hoping that lowering to 35psi it will get closer to reasonable. Any input is greatly appreciated.
#2
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sqrt(new pressure/old pressure) x old flow rate = new flow rate
You're running a TecGT right? Does it support sequential ignition? Do you enter your fuel map in injector pulsewidth or in VE?
current VE entry x (observed afr/desired afr) = desired VE entry
all that being said, it may not be possible to have a great idle w/ 1k cc/min injectors with such a small motor.
You're running a TecGT right? Does it support sequential ignition? Do you enter your fuel map in injector pulsewidth or in VE?
current VE entry x (observed afr/desired afr) = desired VE entry
all that being said, it may not be possible to have a great idle w/ 1k cc/min injectors with such a small motor.
#3
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Agreed, I may not get a great Idle. But before the new motor I could idle at about 13:1 and that was with the 1.8. I am hoping that I can at least get that close.
Those formulas are going to be tattooed on the back of my hand...I am going to be using them constantly.
Those formulas are going to be tattooed on the back of my hand...I am going to be using them constantly.
#4
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Forgot to answer questions.....
I am running the TecGT. It doesn't support sequential ignition. In the Fuel Map I enter in VE. I can view the fuel table in pulsewidth, but I can't figure out how to modify it while in that view...only in VE Display. Of course, I can play around with it some more to see if I can.
Thanks
I am running the TecGT. It doesn't support sequential ignition. In the Fuel Map I enter in VE. I can view the fuel table in pulsewidth, but I can't figure out how to modify it while in that view...only in VE Display. Of course, I can play around with it some more to see if I can.
Thanks
#6
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Forgot to answer questions.....
I am running the TecGT. It doesn't support sequential ignition. In the Fuel Map I enter in VE. I can view the fuel table in pulsewidth, but I can't figure out how to modify it while in that view...only in VE Display. Of course, I can play around with it some more to see if I can.
Thanks
I am running the TecGT. It doesn't support sequential ignition. In the Fuel Map I enter in VE. I can view the fuel table in pulsewidth, but I can't figure out how to modify it while in that view...only in VE Display. Of course, I can play around with it some more to see if I can.
Thanks
#8
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No, that's great. Working with VE is easier than working with PW because you can much more easily and quickly dial in your fuel map. If I needed as much fuel as you, I would want to either run sequential or maybe even staged injection, but I'd put the "primary" injectors in the IM and the big 1k injectors in the stock fuel rail position.
We'll see how it goes, I modified a copy of my file, hopefully I got it remotely close. I adjusted it to add about .5 ms throughout the map. Thanks
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