RX7 STAGGED INJECTION

[TOMMYFD]

Hey guys got an issue and don't know if this is normal or if I have my staging ratio wrong.

My afr's are good but when my secondaries kick in I lean for about 200 milliseconds then my afr's go back to normal is this normal or should i play around with my stagging ratio?

 

 

[Vaughan]

Attach a log and a copy of your tune

[TOMMYFD]

https://drive.google.com/file/d/11q8Rgz5PFKqVijKO4cPuCfGtLPBj6s6p/view?usp=sharing

https://drive.google.com/file/d/1N6Arz7OQ65KwTWW-sJPAkad5eFz_qcKW/view?usp=sharing

[Vaughan]

Little hard to tell with the lambda reading being delayed from the change in injection but you could try extending your Staged Injection Accel Fuel value from 3 injection events to 6 and then take another log to see the difference.

[TOMMYFD]

Thanks I will try the accel fuel and see the difference.

Something else I want to figure out is im out of injectors at 7700@84% duty cycle and I want to rev to 8400.

Im in modelled mode with fp sensor fuel system type and im currently on 48 psi base pressure if I want to increase my base pressure to 56 psi the only thing I have to do is lean out my fuel map or should I change anything else in my settings?

[Vaughan]

don't need to change any settings, modelled mode with fp sensor does all the calculations required to deal with different fuel pressures.

[TOMMYFD]

Just lean out my fuel map?

[Vaughan]

don't change your fuel map, your fuel map in modeled mode is Volumetric efficiency which isn't affected by fuel pressure. If Fuel system type is set to fp sensor you don't need to make any changes when adjusting fuel pressure.

[TOMMYFD]

So how can my injector duty get reduced if my maps are the same?

[Vaughan]

Fuel table specifies the Volumetric efficiency, volumetric efficiency is used to calculate mass of air entering engine, lambda target and stoichiometric ratio is used to calculate desired mass of fuel, desired mass of fuel is converted into an injection pulsewidth taking into account fuel density, injector flow rate at a specified pressure and the current differential pressure.

if you have a specified flow rate at a particular differential pressure you can calculate the flow rate at a different differential pressure and the ECU does this calculation automatically when set up correctly.

[TOMMYFD]

18 minutes ago, Vaughan said:

Fuel table specifies the Volumetric efficiency, volumetric efficiency is used to calculate mass of air entering engine, lambda target and stoichiometric ratio is used to calculate desired mass of fuel, desired mass of fuel is converted into an injection pulsewidth taking into account fuel density, injector flow rate at a specified pressure and the current differential pressure.

if you have a specified flow rate at a particular differential pressure you can calculate the flow rate at a different differential pressure and the ECU does this calculation automatically when set up correctly.

Shouldnt i be in closed loop lambda so the ECU can calculate the desired mass of fuel?

[Vaughan]

2 minutes ago, TOMMYFD said:

Shouldnt i be in closed loop lambda so the ECU can calculate the desired mass of fuel?

Closed Loop Lambda means it can constantly correct for variations between the tune and reality but is not required.

[TOMMYFD]

Thanks a lot Vaughan very helpful so i dont need to do anything just increase my fuel pressure. Thanks again.

[koracing]

This is the beauty of modelled mode tuning with a fuel pressure sensor being used in FP mode.

[Pete_89t2]

One more point to add to this discussion that I didn't see mentioned - you do need to have accurate characterization data on your injectors (i.e., flow @ rated base diff. FP, dead times vs. diff. FP & voltage, SPWA table data) to plug in to your tune so modeled mode can do its thing as well as it normally does.

[TOMMYFD]

https://drive.google.com/file/d/1bZUOM4a9Rj9vwi4h9dFngAjqpfwgp8uH/view?usp=drive_link

https://drive.google.com/file/d/1QXuNZRo0N9t3GIH-0cPt7CxAqFqNk6Jj/view?usp=drive_link

7 minutes ago, TOMMYFD said:

https://drive.google.com/file/d/1bZUOM4a9Rj9vwi4h9dFngAjqpfwgp8uH/view?usp=drive_link

https://drive.google.com/file/d/1QXuNZRo0N9t3GIH-0cPt7CxAqFqNk6Jj/view?usp=drive_link

This are my loggings with 6 inj events on stagged. I go really rich when secondaries kick in then back to normal. What do I have wrong here?

[Adamw]

Your share links have restricted access, you need to go into their share settings and change the settings to something like "anyone with link"

[TOMMYFD]

Sorry try now

[Adamw]

The top link is still restricted, the bottom link works.

[TOMMYFD]

https://drive.google.com/file/d/1YWLNY2QxAwP2MwBorKSAG2NFTbvlVmcY/view?usp=sharing

[Adamw]

Have you confirmed the sec/pri flow ratio is correct by switching between 0% and 100% in the staging table?

Assuming that is correct then just reduce your staged injection accel fuel until you get the smoothest transition possible, dont worry about the lambda so much, but more the feel.   

Also, (not related to staged injection) you should put non-zero values in your accel cold correction table as you have no accel fuel at all right now.  

[TOMMYFD]

I didnt confirm with a 0% and 100% iIjust did the calculations as the help file is saying.

I have no clue of what numbers to put in my accel cold correction table how will I calculate those?