knock logic - tutorials available?

FlashPro questions & answers specific to the FN2 European Civic Type R
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typer86
Posts: 342
Joined: Sun Oct 28, 2012 3:17 pm

knock logic - tutorials available?

Post by typer86 »

Hi Hondata,

finally I would like to test the knock logic in my calibration. Did you have further documentation, guides which you can share? It is hard to understand your descripion in the manual without real examples how to setup the table.

Tuning knock control:


Main ignition tables - decrease the ignition timing in the main (MBT) ignition tables at rpm and load points where the knock ignition limit tables are negative.  This will then allow us to use the factory knock control more effectively.
Q: Do you mean the ignition low/high tables? I would not touch anymore this table because it is finally tuned right now...
Q: In my case I have tuned the car with knock ignition limit set all tables to 60
> Which way I must go now???


Knock ignition limit - use low values where the engine is likely to knock.  For forced induction engines on pump fuel we can assume they are tuned to the edge of knock, so columns 9 to 10 and should be 5 degrees or less, and columns in boost should be zero.  Note that you should always adjust the main ignition tables if increasing values in the knock ignition limit table.
Q: This is which confusing me totally - First section you write the main ignition table must be decreased
Q: If I lower / zero the table what is the expected result?
> zero positive values = retard or advance ignition too?
> negative values = advance the ignition of the gap to zero?
Q: Can I set the knock ignition table all with the same value to avoide bumpy table?
Q: Do you mean this? The attached screenshot is what I understand (mockup)
knock_1.PNG
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Knock sensitivity - increase the knock sensitivity (reduce the values) in columns 4 and above.  For engines with noisy cams, headers etc, you may need to reduce the sensitivity (increase the values).
A: I understand

Knock retard - use a smaller knock retard than stock - 4 to 10 degrees.  The lower columns (6 and below) will have little effect on knock retard as the knock ignition limit should be much higher than the MBT ignition timing in these areas.
Q: What this table should do?
How I understand the retard table:
If a knock will be determined, the ECU will retard in this section of table around xx degrees? So in WOT 10 degrees retard is to much I suggest to start with 2 to 4 degrees as max.!


Knock control - on newer vehicles, knock control will start out high and slowly come down as the engine runs through normal driving conditions.  You can expect close to full knock retard right after programming the ECU.  To decrease knock control on the dyno, simply hold the car at a steady RPM and, as long as there is no pinging, the knock control will gradually come down

If K.Control is greater than 0% and the maximum ignition timing is less than the MBT timing then the difference between the knock ignition limit and maximum ignition timing will show as a knock retard value.
 
Q: K.Control is stable on 55%. (Which you can see in the screenshot from my last log)
But I have ROZ98 fuel in my tank so why K.Control did not determine 20/25%?
K.Control 0% = ROZ 100+ (in Germany: Premium SuperPlus from Aral 102 octan or Shell VPower100 octan)
K.Control 25% = ROZ 97.5/98 (in Germany: SuperPlus)
K.Control 50% = ROZ 95 (in Germany: Super)
K.Control 55% = ROZ 93.5 (in Germany not available any more)
knock_2.PNG
knock_2.PNG (88.54 KiB) Viewed 2995 times
You can see I did not understand the knock logic based on your documentation in the FP help...
If you can provide a short screencast of a typical tuning cycle I think it will answer a lot of questions because we can see the steps what is to do.
Otherwise I suppose what the option should do and the risk is high to damage the engine caused by high ignition advance....

Thanks for help - I hope I will understand the knock logic in the future (my last goal to setup a 100% tune)
typer86
Posts: 342
Joined: Sun Oct 28, 2012 3:17 pm

Re: knock logic - tutorials available?

Post by typer86 »

I have testet the setting right now. I can see, the K.Control goes down slowly after activate the knock Ignition table.
I don't know but after driving few rounds can you confirm the throttle tip in is going smoother without active knock ignition table?
I can not feel the little "jerk" anymore without enabled knock control.
knock_3.PNG
knock_3.PNG (237.87 KiB) Viewed 2986 times
Next I will test this configuration:
Any considerations before I test it? Because now I will test negative values.

knock_4.PNG
knock_4.PNG (111.4 KiB) Viewed 2986 times
mladjan
Posts: 120
Joined: Fri Sep 23, 2016 7:16 am

Re: knock logic - tutorials available?

Post by mladjan »

Thumbs up for questions, this part is black magic for me too.
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Hondata
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Location: Torrance, CA
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Re: knock logic - tutorials available?

Post by Hondata »

Can I suggest that you break you post down into smaller, small specific questions. At the moment it is very general and also when I look at it I have trouble determining what is a question, what is something out of the help file and what is a statement.

As a starting point you must understand how Honda knock control works and how they create the knock ignition limit tables. It only is designed to compensate for differing fuel quality on stock engines. For the most part, with the FG/FN2 at least, if the fuel quality is consistent than knock control is not that useful for us. It is only really there for the owner how puts in low octane fuel on a stock vehicle.
Hondata
typer86
Posts: 342
Joined: Sun Oct 28, 2012 3:17 pm

Re: knock logic - tutorials available?

Post by typer86 »

Ok - so thank you for your Reply.
So we can say set all to Zero? Because it is nothing to "compensate" in our case... :D
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