BRZedit Fuel Trims, Closed to Open loop transiton

[jamesm]

Originally Posted by Sportsguy83

I would like to see this

i am in the process of writing one up using yikes' spreadsheet... it's really pretty simple though a monkey could do it (if said monkey had opposable thumbs and could open excel).

you can just use the yike's spreadsheet instructions as a guide. the key difference being that 'af/cor #1' is STFT, and 'af learn #1' is LTFT, and pre-filter your log for fuel system status 2... 4 is open loop. then in yike's spreadsheet, just prefill all the columns with 'CL' in the 'CL/OL' column so the filtering will still work. then just paste in all the values (including your maf table), click 'filter', then 'plot maf changes', apply them, log again and repeat.

using this method a few times got me from +/-20% LTFT to +/-2%... so it works.

[diodelphi]

thanks all
useful information

[Wayno]

Is there any value in simply making CL AFR's follow OL within a couple of points?

Downsides besides economy? Will it effect LTFT learning?

[Kodename47]

IIRC if you set it all to 14.7 (0 in Romraider) then you effectively switch off LTFT. There's no point in setting it below 14.0 as you'll be in open loop, that's if your minimum open loop enrichment is set to 14.0 as it is stock. Mine is a mirror of my OL fuel map, one of my spreadsheets generates this for you.

I guess delays play a part, I've set all mine to 0 to ensure it switches to open loop if the fuel map dictates less than 14.0, however if you have the standard delays then it may be worth allowing values down to 13.5 (-1.2) so that the CL tries to richen up a little. I'm not sure how well that works though as I've not tested it.

[Wayno]

Ok, it's good to know someone else has made CL mirror OL.

I can think of one reason why the delay is there - so that the ecu can learn the highest bracket ltft.

I limited CL to 12.5, not that it will likely ever hit those cells.