TnF Posted August 6, 2017 Report Share Posted August 6, 2017 (edited) Hello guys. I have my engine running Injector Dynamics 1050x injectors @~3bar base fuel pressure on a 1:1 fuel pressure regulator. Was running them on a 2D injector dead time table with correct short pulse adder table, and last week i've got a 10bar (absolute?) fuel pressure sensor of which i've hooked up and wired correctly. Now i am doing the map setup to change to the 3D injector dead time table and i am confused (already changed Fuel system type from MAP referenced to FP sensor, that is correct right?). The following data i have is 100% correct (fuel pressure vs voltage vs injector lag time). Now should i use differential fuel pressure instead of fuel pressure? If i do this shouldn't i have to subtract 3bar (300kpa - aka my base fuel pressure) from the x-axis values shown in my screenshot? Or does the model internally calculates this correctly the way i have it set up in the screenshot right now?You see my "problem" is that if i use differential fuel pressure this means in case the BASE fuel pressure changes for whatever reason the system will compensate incorrectly and it will require re-adjustment of the x-axis values. The way i see this to function correctly is if the model when set up to MAP referenced, to take account the 3d table i have below automatically assuming i gave it a correct base fuel pressure.I am pretty sure i am mistaken somewhere in my thinking because i am confused, so if you can please shed some light i would really appreciate it! edit: btw i've noticed the 3d table has 2 decimal places instead 3 decimal places of the 2d table, am i losing something?edit2: After thinking it about a lot i think i've got it, just changing the x-axis of this table in my screenshot from fuel pressure to differential fuel pressure should net me the correct results! This is because for example if i had my base fuel pressure to 300kpa, the engine idle to -50kpa MGP then the fuel pressure would be 300-50=250kpa and then the DP=250-(-50)=300kpa which can looked up on this table. This means if base fuel pressure = differential fuel pressure on 1:1 regulator meaning for any change it will be compensated by this table! Correct me if i'm wrong Edited August 6, 2017 by TnF Quote Link to comment Share on other sites More sharing options...
Steve Posted August 6, 2017 Report Share Posted August 6, 2017 Your thinking in the end is correct.You set it to differential pressure and you are good to go. Quote Link to comment Share on other sites More sharing options...
TnF Posted August 7, 2017 Author Report Share Posted August 7, 2017 Your thinking in the end is correct.You set it to differential pressure and you are good to go. Yes indeed, tested it later in the afternoon, everything works as expected Quote Link to comment Share on other sites More sharing options...
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