bubba2533 wrote:Have you changed the delay/transition volume values? They slow down the changing of the flex percent significantly.
All flexfuel tables are direct copy from -04 L59 PCM.
I doubt there is so long delays, they have effect after consumed 36 liters gas?
Yeah, that's not an issue. But some people think they put a little fuel in and cycle the pump to change the flex percent. That will work if you zero the delays out, but if you don't run the engine it will change very slowly.
"All the tables" depends on which XDF you are using. It would probably be better to start with a flex fuel enabled tune that was known working.
LS1 Boost OS V3 Here. For feature suggestions post in here Development Thread. Support future development ->Patreon.
Hiya guys,
Sorry to butt in but am curious about the flex fuel stuff. I have the same concern as bubba. I have a couple guys that would like me to set their vehicles up for flex and am working on it. I changed all the parameters in the calibration and according to the efilive scanner everything seems to work. However, my concern is what if the OS doesn't make it happen? I haven't dyno'd or verified with a wide band YET and am very open to any help or anything I should be watching.
In-Tech wrote:Hiya guys,
Sorry to butt in but am curious about the flex fuel stuff. I have the same concern as bubba. I have a couple guys that would like me to set their vehicles up for flex and am working on it. I changed all the parameters in the calibration and according to the efilive scanner everything seems to work. However, my concern is what if the OS doesn't make it happen? I haven't dyno'd or verified with a wide band YET and am very open to any help or anything I should be watching.
I have looked at the OS and there are dozens of places that uses flex percent to do a table lookup that HPTuners and EFI Live do not have defined. It would take quite a long time to determine what each one of them does, so it really isn't worth the time when you can start with a tune that already had Flex Fuel enabled.
Sadly my application (V6) never came with flex fuel enabled, so I've enabled it myself. But my vehicle is not my daily driver, so I can deal with some issues until I can figure out what tables need modified.
LS1 Boost OS V3 Here. For feature suggestions post in here Development Thread. Support future development ->Patreon.
bubba, thanks for the reply and all the hard work you have done on this new boost OS. I haven't had a chance to play with it yet but I am looking forward to it.
Over the next few weeks I will be digging deeper into the flex stuff and I will keep you all apprised of what I find. Like you say, it's definitely easier to start with a flex file. As you noted though, sometimes we might want to take an existing file and add flex to it.
Here is a report file from one of the flex fuel files I have via TunerCat. It shows all of the parameters I can change. I don't have the .bin file handy so if you would like that I will "burn" a 'puter and suck it out.
The 6125 os has the exact same flex fuel tables as the 7603 flex fuel. The only one I haven't looked into is a table that has something to do with the cat conv.