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Hello, It has been a month since i have completed installing a JDM K24A on my 04 Element. So far all is working properly thanks to Ktuner. It is my daily driver, and i am trying to tune for max economy, but feel no dyno tuning is necessary for my application. I an generally happy with highway and high RPm performance but low end stop and go will need little tuning. I have been running and loggin both RSX type-R PRB base, and also Element PZD base. RSX base map seems to have a flat spot/hesitation on low load between 1500-2000 and shfting to 2nd gear, and Element base map is ok except i had to adjust Vtec engagement point higher, and generally little worse fuel economy than RSX base.

So the question is how the base fuel, fuel in cylinders 1-4, and Short term Fuel trim is related ? on RSX base, Fuel in cylinders are 500-600 points higher than base fuel, while showing +/- zero STFT. on Element base, Fuel in cylinders are 350-400 points higher than Base, but showing average of -20 to -26 short term fuel trim. So which is better starting point and how do i adjust for this ? Do i need to up the fuel map so the base and fuel in cylinders are closer ? why does Element baser shows minus STFT when the base numbers are closer ? Can i adjust just STFT ? Do i need to run a long on open loop and monitor AFR for batter base map ?

On 1500-2000 RPM on RSX map, AFR shows i am running little rich. Do i just try trimming a little on the fuel map, and test ?

BTW, JDM K24A runs so smooth and quiet overall with Ktuner in comparison to my old K24A4/stock PZD

Thanks !!

Zero fuel trims are good. The ECU pulling 20% of fuel to reach the commanded air/fuel means it was too rich.

You can alter fueling in the fuel table, yes.

Thanks.

with zero fuel trim, doesn't base fuel and fuel in cylinder number should be closer ? why fuel in cylinder is always 400 point higher that base ?

Base fuel is the fuel table value. Fuel per cylinder is the final output. If you don't understand the correlation or that the fuel table isn't the only thing involved with calculating final fuel values you may want to seek the help of a professional tuner so you don't end up damaging something.

So sorry if it is a dumb question again. I just to understand the relationship between base fuel and Cylinder better. You are saying there are many other major factors other than RPM, Load,Temp,AFR,and WBO2 to calculate final fuel value ?
so do I just focus on Short Term trim reading to see if the base fuel map is not too rich ?
For example,
on Element map Log, Base Fuel was 1998, on Cylinder reads 2401, but STFT says -20,which is cutting 20% off to reach ideal AFR, then why Fuel in cylinder is much higher than base map ?
on RSX map log, Base fuel was 1988, on cylinder was 2598, but STFT reads zero, but why the difference is so much greater ?

Thank you one more time !

If STFT is -20 the final fuel value per cylinder already has that applied. 197 points is not much. The difference could literally be from any of the inputs you mentioned, RPM, MAP, etc. If you expand the data list you'll see that those values equate to an injection time.