Knock Control

Civic 2016+ 1.5 Turbo
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LordMothy
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Knock Control

Post by LordMothy »

I've been reading about how to adjust the knock ignition limit for advancing the timing. After reading it a couple of times I think Ive got a resonable graspe on its basic operation. The knock control % and the Knock retard make sense now. It appears that Honda did a decent job making the timing versatile.

Ive been doing some exercises using the "Knock Igniton limit" and have been proceeding with caution. I no longer have a dyno at my disposal to measure when enough is enough but my concern is that the "Knock Level %" is too perfect and I've not even recorded any knock counts on any cylinder ever. Should I be suspicious or is the timing just that conservative? Will I see elevated Knock level % before Knock counts?

Also, does anyone know how the engine management decides what octane your using? I haven't figured out how it works just yet. I do know my knock control % is accurately representing 93 octane.
Jun43
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Re: Knock Control

Post by Jun43 »

if you look at the datalog sensors list, knock count is not recorded
LordMothy
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Re: Knock Control

Post by LordMothy »

How bout that. I assumed I was able to monitor that. I’d sure hate to rely solely on audible knock.
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Hondata
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Re: Knock Control

Post by Hondata »

Not all ECUs have a threshold where they consider knock to occur, since knock is not a discrete event.
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LordMothy
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Re: Knock Control

Post by LordMothy »

Understandable, knock isn’t some line drawn in the sand for sure. Would you discourage any timing adjustment without the use of a dyno? What process do you use for identifying when you’ve reached the most that can be done before raising the octane?

In the past I’ve always tuned for peak power levels and then dialed back a bit for safety.
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Hondata
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Re: Knock Control

Post by Hondata »

With the turbo 1.5 the ECU handles the timing fairly well. The best indicator is looking at what the knock control is doing. If it goes up on one area, then consider lowering the knock ignition limit in that place. You want the knock control to be as low as possible.
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LordMothy
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Re: Knock Control

Post by LordMothy »

Awesome! Thanks again.
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