Question about fuel system upgrade tune

[AllenZhangFE3]

Hello Hondata,

I've upgraded the fuel system on my 2022 1.5T non-Si Civic. I’m using the high-pressure fuel pump and injectors from the RDX 2.0T, specifically the 6B2 model and the Si intake camshaft. I’d like to ask for guidance regarding fuel tuning:

Should I use the fuel trim function to globally reduce fueling (e.g., reduce by 10% on cylinders 1–4) to maintain consistency with the mass flow calibration in the AFM table?

Or would it be more appropriate to directly tune the AFM table to achieve proper fueling behavior?

Looking forward to your expert advice. Thank you!

[Spunkster]

We do not have a fuel system or the settings to tune a different fuel system in the non-SI Civics.

[AllenZhangFE3]

Thank you for your reply. I understand that this is not a fuel system upgrade officially provided by Hondata. I just want to understand from a theoretical perspective: when using a larger high-pressure fuel pump and larger injectors, should the adjustments be made primarily through overall fuel trims, or by tuning the AFM calibration table, or is it necessary to use a combination of both? Thank you.

[Spunkster]

The options needed to make it work properly are not available for the non-SI Civic.

[AllenZhangFE3]

Thank you again for your response. Could you please let me know which feature or parameter in the Si model enables improved compatibility with the upgraded fuel system? I would like to reference calibrations from other models and hope this feature can be implemented in non-Si models too. Thank you!