Closed Loop Lambda table

[integrale8v]

Hi.

 

Tables on the closed loop lambda: "Ftrim Limit +-" would be nice. So one can for example add/subtract  different max % at different rpm/loads.   And option to set different max + and -.

[Scott]

Thanks for the suggestions, I will pass them on to our engineering team.

[mapper]

May i add to have 4d and 5d tables and many other tables setup as afr compensation overlay. For example i like to add some fuel at high IAT's and high gears.

If I use full time closed loop control, i need to adjust the afr target accordently. Otherwise the closed loop will remove the additional fuel on high  iat ( overlay target already used for gear compensation).

similary on warmup of the engine. Most engines run smoother during warmup of we use a bit richer mixture. 

 

[Scott]

Hi mapper,

Thanks for the suggestion. I will pass it on to the engineering team. Are you aware of the 'Lambda Target Table Overlay'? This is not as comprehensive as what having multiple tables is, but does allow you two more conditions upon which to alter the Lambda target.

[mapper]

yes as I've written I'm usually use the target overlay already to do gear compensation (Lambda Target Table Overlay spanned Gear or Speed vs RPM) 

So i need more tables to alter the target. Otherwise i can't use full time closed loop control. Usually it's a good idea to rich mixture up on situations that are prone to knock. (high temps and loads) 

 

[Ducie54]

yes as I've written I'm usually use the target overlay already to do gear compensation (Lambda Target Table Overlay spanned Gear or Speed vs RPM) 

So i need more tables to alter the target. Otherwise i can't use full time closed loop control. Usually it's a good idea to rich mixture up on situations that are prone to knock. (high temps and loads) 

 

If your max lambda Ftrim limit is set to +- 5% and you want another 5% trim for high temps why cant you just increase the mixture 10% ? 

[Ducie54]

May i add to have 4d and 5d tables and many other tables setup as afr compensation overlay. For example i like to add some fuel at high IAT's and high gears.

If I use full time closed loop control, i need to adjust the afr target accordently. Otherwise the closed loop will remove the additional fuel on high  iat ( overlay target already used for gear compensation).

similary on warmup of the engine. Most engines run smoother during warmup of we use a bit richer mixture. 

 

In the modeled mode doesn't the IAT temps get automatically compensated as part of the Gas law? Theoretically If you set the IAT as a 3D table with gear you should be able to Increase fuel compensation over the closed loop Ftrim limit.   

[mapper]

In the modeled mode doesn't the IAT temps get automatically compensated as part of the Gas law? Theoretically If you set the IAT as a 3D table with gear you should be able to Increase fuel compensation over the closed loop Ftrim limit.   

Right the fuel model keeps the AFR constant over a wide range, assumed the charge temp approximation table is tuned properly. Regardless of this, i usually like to richen the mixture a bit up at high IAT's, to cool the combustion chamber and to prevent detonation. 

Sure you can  add 10% to overcome the closed loop lambda system by 5%, it's a workaround. 

 It's not that straight forrward as it could be with targed compensation and i it's not the way the CL Lambda is meant to work. So i like to have 6D target compensation. 

Maybe the LINK engineers can add an axis option on the 4,5 and 6D tables. 

 

[Dave Kriedeman]

So in short a custom version of STFT and LTFT with extra compensations and everything should be covered.

Regards

Dave.