Hondata

Hi.

I would like to know why exists differences in the injection timming between the stock calibrations Civic-Si-RRD-1-M12 and Civic-Si-RRB-1 for Civic Si 2006-2011 South America.

I have this question because after flashing the Civic-Si-RRB-1 (stock equivalent) with modifications in AFM flow and disabling the O2 second sensor, was necessary ~13.5ms of injection time to reach 0.88 lambda at ~7500RPM and full throttle. It seams higher than normal for me, but it almost matches with the injetor timming of RRD calibration. Today in Brazil, premium gasoline is E25.

Now I don't know if it's a problem in my car (maybe the injectors or the fuel pump) or if the fuel timming should be a little higher for Brazil.

My car is a Civic Si 2008 with the ECU 37820-RRD-M11, Skunk2 Alpha header and K&N V2 SRI Intake, injectors and fuel pump stock. I uploaded a datalog to show better what is happening. Now I'm running only in closed loop, with lambda targets above 0.85, because my injectors are reaching 95% of duty in some cases.

Thank you in advance!

You would have to ask why Honda tuned them differently, as we are using what Honda did.

Thanks for the answer, makes sense!

Is there any guess why it's different? For my ECU, which tuning you think should be the correct one?

what is your ECU part number?

37820-RRD-M11

Then your best bet would be to use the RRD based calibration.

I want to bring you the end of this story. The RRD was the right tuning, and the injector timing was correct. My vehicle had a fuel pump problem, and fuel pressure would decrease as demand increased. I replaced the fuel pump, and now everything works perfectly!