DFCO +25% trims - anyone raise the DFCO threshold RPM?

[WS6FirebirdTA00]

First, I am curious if upping the threshold would even work. If the entry and exit don't reset per gear I don't see it helping.

The point of my post was to see if anyone has done anything to address the +25% trims on DFCO re-entry. I see nothing in there to adjust that transition (2018 Sierra) and from searching I see others in the same boat.

I have been tempted to disable DFCO and drive like that to see if it affects economy at all. I am also curious how it will affect the normal engine braking/control when it is actually useful.

One thing that is annoying is while trying to cruise having it pull speed, but it is also useful when using cruise since these trucks don't have adaptive cruise.

I am annoyed by the 25% added fuel, then the rich condition that happens after that, leading to a lean spot right before it settles back in. Trying to look at the MAF STFT error without disabling DFCO is completely useless. I may try to disable for a tank to see how it feel for normal cruising (since I didn't pay much attention when tuning the MAF) and see how it affects fuel economy. I was just looking to see if anyone else did something similar and what their results were.

[TriPinTaZ]

First, I am curious if upping the threshold would even work. If the entry and exit don't reset per gear I don't see it helping.

The point of my post was to see if anyone has done anything to address the +25% trims on DFCO re-entry. I see nothing in there to adjust that transition (2018 Sierra) and from searching I see others in the same boat.

I have been tempted to disable DFCO and drive like that to see if it affects economy at all. I am also curious how it will affect the normal engine braking/control when it is actually useful.

One thing that is annoying is while trying to cruise having it pull speed, but it is also useful when using cruise since these trucks don't have adaptive cruise.

I am annoyed by the 25% added fuel, then the rich condition that happens after that, leading to a lean spot right before it settles back in. Trying to look at the MAF STFT error without disabling DFCO is completely useless. I may try to disable for a tank to see how it feel for normal cruising (since I didn't pay much attention when tuning the MAF) and see how it affects fuel economy. I was just looking to see if anyone else did something similar and what their results were.

I never found a way to make this go away. It seems its the norm in GenV stuff. What really sucks about it is that the ECU limits spark advance via Torque Management advance during this little moment of DFCO exit and sometimes I can feel it because I want 30+ degrees of timing but its being limited to 20 degrees. As soon as the DFCO exit ends, the timing shoots right up to 30+ and I can feel the engine smooth out. I've mitigated most of it with some timing and VT changes but not all of it. I could tune my minimum spark table to mitigate the rest of it but I just think that would cause another anomaly under other conditions.

I don't see a way to change anything relating to fuel right after DFCO exit. You can change the entry and exit torque requirements and even edit the enable disable via speeds like the C6 Z06's used but nothing that changes how much re-entry fueling is added. I can only assume the ECU sees a very lean condition(O2's) as soon as you touch the throttle because the injectors are pretty much off and immediately goes to +25% STFT until the O2's can catch up. I have confirmed this behavior is present in bone stock E92 Corvette's/Camaro's, but you don't really feel it. On my C7 Corvette I found some relief by lowering virtual torque below 3000RPMs to bring the calculated torque back down to near stock levels in that area. Now it pulls less timing via Torque Management Advance during this situation and has mitigated a lot of the feel when it jumps back to stoich. For the record I was only experiencing this issue at low RPM's, typically between 1800-2600 RPM's and under 20mph.

[WS6FirebirdTA00]

Thanks. I will check out messing with that.