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Is there any benefit to switching from Global to Per Cylinder Knock control, or vice versa? I have seen it done both ways, but am unsure of which method would be the 'best' per-se. Global is factory on my '15 Eco. However, wouldn't it make more sense to change timing/knock per cylinder as needed vs. pulling the same timing from every cylinder in the global method?
I have been told - Global is best for safety - Per Cylinder is best for power
Some of the newest ecoboosts come with Per Cylinder from the factory.
From what I've seen, Ford tends to use Global on multi-bank, Per-Cyl on single bank vehicles.
I'd assume this has to do with how well they can window the sensors to determine what cylinder just fired.
The 4-cyl Ecoboost have 2 knock sensors and 4 cylinders, plenty of room to window. You'll only ever have one cylinder firing at a time.
6 cylinders will always have an overlap so perhaps they just determined experimentally that they couldn't get per-cylinder to function or window reliably with the cylinder to sensor ratio.
Thank you guys! I appreciate the insight and explaination. I have been experimenting with mine and noted two different knock sensor settings on a couple of tunes i'm referencing. My thought logic was that originally Ford used Global on this 3.5L, so indeed there must be a reason, and therefore i'll also continue to use global.
Some of the 2.7's come with per cylinder set from the factory.
Interesting!
as mentioned, you are able to log per cyl knock activity. say cyl 4 runs hottest/leanest (you may reduce timing per cyl)