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Something that I have never really found a straight answer to. What exactly does this table do in the grand scheme of things. By changing the numbers, what does that tell the ECM to do. For Example, Say you have 24 lb injectors installed and you set the table to 30 lbs. I realize it will be running lean, but why.
That table should never change unless you actually changed the size of the injector.
You would never change it to a larger or smaller value if the injectors don't actually flow that rate at whatever PSI the vehicle is running for fuel pressure.
For example, changing the size to 30lb/hr when the injectors can only do 24lb/hr at 58psi would give false information to the computer and data logs. If the table was set to that 30lb/hr and the engine was making decent power to show say 90% injector duty cycle but in reality they are smaller injectors. They would be been well over 100-110% duty cycle because you lied to the computer, this is where engine damage could happen.
Ok, lets try a different example. My engine came with 24lb injectors, and I swapped them out for 33 lb injectors. I change the IFR table to 33 lbs. What does the ECM change to deal with the additional fuel. Is this just an arbitrary number that gets made up for by increasing or decreasing VE numbers.
You would correct the airflow model for the change in injector size. Correcting the MAF curve if you are running a MAF and tuning the VE table as required.
Don't forget you also need to change the min injector pulse, short pulse adder, offset vs volts so the computer knows the data on the injectors.
Best answer I’ve seen
https://forum.efilive.com/showthread...l=1#post127541