"Enhanced RPM" parameter on Closed Loop control algorithms

[pannetron]

There are two parameters in the latest version of the VCM editor that I'm unfamiliar with: Fuel/Oxygen Sensors/Closed Loop Enable/Enhanced RPM and Simplified RPM. The note mentions that at RPM below the Enhanced RPM limit the ECU uses "enhanced closed loop algorithms" and at RPM over the Simplified RPM it uses O2 sensor rich/lean thresholds. What are the "enhanced algorithms?" A stock ZR1 tune has 3000 and 3100 RPM for those parameters; my 430 HP crate engine E67 has 0 for both values so I assume my ECU never uses those "enhanced" algorithms. Should I care? Maybe my crate ECU lacks those enhanced algorithms?

Back in 2017 there was a forum post (https://forum.hptuners.com/showthrea...t=enhanced+rpm) asking for these two additional parameters among many others.

[Cringer]

There are two parameters in the latest version of the VCM editor that I'm unfamiliar with: Fuel/Oxygen Sensors/Closed Loop Enable/Enhanced RPM and Simplified RPM. The note mentions that at RPM below the Enhanced RPM limit the ECU uses "enhanced closed loop algorithms" and at RPM over the Simplified RPM it uses O2 sensor rich/lean thresholds. What are the "enhanced algorithms?" A stock ZR1 tune has 3000 and 3100 RPM for those parameters; my 430 HP crate engine E67 has 0 for both values so I assume my ECU never uses those "enhanced" algorithms. Should I care? Maybe my crate ECU lacks those enhanced algorithms?

Back in 2017 there was a forum post (https://forum.hptuners.com/showthrea...t=enhanced+rpm) asking for these two additional parameters among many others.

Did you ever find any more info on Simple vs Enhanced topic?

[pannetron]

No, nothing :-(

[07GTS]

i noticed on startup i wanted to have it a little richer but it seems to be in an ''OL stoich'' which i found strange, it was using the trims before CL was enabled quite annoying when u need a little more fuel, i thought that enhanced rpm setting might be the cause as it was on might have affected it but seems not but that disabled made it worse, not sure what it does

[verlon]

That's not 'enhanced' or 'simplified' algorithm. Calculations and closed loop logic remains exactly the same.
The difference is how frequent closed loop calculation routines are executed.
In 'enhanced' mode (event mode really) routines are executed for every cylinder intake stroke.
In 'simplified' mode (timing mode) routines are executed periodically every 12.5ms (or 80Hz).

If you set both RPMs to 0 you'll get just timing mode only with slightly faster idle CL responce.

[Cringer]

That's not 'enhanced' or 'simplified' algorithm. Calculations and closed loop logic remains exactly the same.
The difference is how frequent closed loop calculation routines are executed.
In 'enhanced' mode (event mode really) routines are executed for every cylinder intake stroke.
In 'simplified' mode (timing mode) routines are executed periodically every 12.5ms (or 80Hz).

If you set both RPMs to 0 you'll get just timing mode only with slightly faster idle CL responce.

That is great info! How did you figure this out? Is it documented somewhere?

[verlon]

That is great info! How did you figure this out? Is it documented somewhere?

Reverse engineering.

[pannetron]

Reverse engineering.

Wow, good job on reverse engineering and thanks for that info!