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Base fuel pressure help

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I have been tuning a Mitsubishi NA engine from a couple of days. I'm using Link G4+ with modeled Fuel Equation. But the base fuel pressure has to be setup at 100kpa else engine won't start. What would be good point for minimum effective pulse for 240cc stock injectors.

100kpa on returnless style fuel system. Is something wrong or am I missing something

hello you will need 3bar at least to hold injectors closed and allow for enough fuel pressure while tuning the top end

post up your base map for us to check over or email tech@linkecu for the tech team to look over with a note as above

Regards Ross

Hi, thank you. I have attached the current map file. I tried by setting base fuel pressure at 300kpa. But engine won't fire. If it's set to 100kpa its starting without ay difficulties and stays at good idle. As you said, I didn't go WOT Tuning cause I don't want to take chances until I'm sure about fuel pressure.

Attached Files

hello, i have made some changes for you to look at in compare mode, don't just drop this map in and try it I want you to use the compare and then try and see what i have changed and why i have changed it. i also want you to get a timing light and recheck the base timing because I have not seen a G4+ need that offset number to get 10 degrees timing they are normally 0 offset to see ten deg on the timing light again check it please don assume your tuner has set it correctly, i have altered the ignition map to roughly what i would expect to see if the base timing was set correctly

Regards Ross

Attached Files

Fuel density @ 20⁰C in my map was almost 1/10th of actual fuel density. Basically the entire fuel calculation itself was wrong. Omg. If I had completed the Tune, I think it wouldn't have had a happy ending . Thank you so much.

Fuel charge cooling Co efficient, I think should revisit to Check accuracy of Tune by changing lambda Value of a tuned cell. If the measured lambda Value is richer I should address it by reducing charge cooling coefficient and if it's lean I should increase charge cooling Co efficient. It's important because it effects the VE drastically when ambient temperature changes.

I will check Timing offset once. I'm not sure. The person who assembled engine said the offset Value which I entered into the map.

Ignition table values which you suggested looks fine.

I will make appropriate changes.

Thanks a lot. If you wouldn't had pointed it out, I would had definitely overlooked.