Knock Octane Modifier Calibration

[reubone]

Hello yall,
After finally getting settled where I wanted to power wise I decided to make sure that the octane modifier still worked to reduce power when need be. I filled up with 15.5 gallons of 87 octane and drove on it for a few days. After which I hooked up the computer to find that the KOM had settled on .43 as its new number instead of 1 that i see on 93. I expected to see -1 or at least 0. Well then I decided to change the initial KOM to -1 to see if it would stay there on 87. After a few days it was back up to .43 again. So now here is my question, Should I try to recalibrate this so that 87 will trigger -1 or just leave it alone?

Side note,
My wife was driving while on a shopping trip. I was in the passenger seat answering emails and the and all of a sudden she hollers out "RACE" and floors it. This Scat Pack rolls up beside and continues to walk out on us but it was closer than I though it should have been. After she said" Hmm this seems down on power" then casually turns the radio up a little and starts singing. I thought I was going to be buying an engine for sure but no issues. No coughs or heating issues or rattle can sounds or anything. Just a noticeable drop in powers and an L to a Dodge.

[Seishuku]

0.43 would be under the starting nominal 0, so you're blending about half of the normal LSPI and half the low LSPI limit tables, along with whatever timing reductions... So the low power feeling doesn't surprise me.
It went from nearly 400 ftlbs torque to probably 250. (I would actually be interested in a log of this!)

I wouldn't mess with how OAR functions, it appears to be working correctly, just let it do it's thing.

[reubone]

On the mustangs, it is a little different. With a reading of .43, I actually between high and nominal LSPI tables instead of the low and nominal. My inferred octane rating was reading 91 octane. Im not concerned about the power loss, I expected it but I didnt think it was pulling enough power out. If it was -1 on the low table, it will really be down on power but my thoughts were that it would be safer for 87.

[Seishuku]

OHHHH, that's right... You're a few years newer than my mustang, I forget they flipped it so -1 is worst and 1 is best.
On 17 (I think) and older it's the other way, -1 is best, 1 is worst.
Sorry about that, you're right.

It's possible that it was seeing enough knock to pull far more timing than needed for a safety margin, then slowly ramp it back in.
I've seen this happen on my car in the early tuning stages, kind of like homing a 3d printer, drive to the home switch, back off, then drive back in much slower.

But if OAR is only .43 on 87, the ECU must feel fairly confident in the timing correction. I would still be interested in a log showing cylinder knock...
It's also possible that it's still adjusting to the octane too, I've had times where it took over a month to get it to adjust after a KAM reset.

Might not be a bad idea to adjust the learning parameters in spark->retard, time to learn and max load (or whatever they're called, I'm not at a computer).

[reubone]

The things I changed for the knock learning is the rate at which it adds timing in the absence of knock. Also the max load I believe is set at 2.0 instead of 1.7. I'm wondering if a gallon or so of 93 was enough to increase 87 to 91. It doesn't seem likely but I wonder. Also I had a thought about intake temp. Since I am now intercooled properly that has to have an effect on knock. Perhaps it would read -1 if I were still on the stock intercooler.

[Alirayshan]

Dear sir;

Tell me how to set those tables in the scanner in case of knocking or knock retard, because I have more than 27 tables in both Broderline and MBT as well as octane adjucetment table, because this platform is not as usual, it has high octane and low octane, it differs.
Untitled2.jpgUntitled1.jpgUntitled3.jpgUntitled4.jpgUntitled5.jpg

My car2212022 After1.hpt

Best regards & Thanks

[reubone]

Here is what I do.
Step 1. Make your first data log to see if you have any knock or not. If not, move on if so go to step 2
Step 2. Ignore the MBT and OCTANE MODIFIER tables for now. Only regard the BORDERLINE tables 1-14. Also a table to consider is Cylinder Pressure Limit. If you can in fact do this, continue reading. If you still think you need to start with the tables are supposed to be ignored, start over with step 2. The Borderline tables ASK for a certain degree of timing so this table is where the commands are coming from. Cylinder pressure limit is often your first limiter so reference this if your spark source is Cyl Pressure limit on your data log. Upping this table will allow more timing to be asked for up to a point. it can also be lowered to limit total timing.
Step 3. In the scanner, add these channels.
mapped points 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14
Timing Advance
Knock Octane Modifier
Knock Cyl 1 (+Adv/-Ret)
Knock Cyl 2 (+Adv/-Ret)
Knock Cyl 3 (+Adv/-Ret)
Knock Cyl 4 (+Adv/-Ret)
Air Load
Engine RPM
Spark Source

These are the bare minimum tables required to track and plot your timing tables and associated knock or lack there of.
Step4. Build your tables to mimic the borderline tables in your calibration file and set it to plot knock. Set your filter to only plot above 60% utilization and a certain throttle % like say 20%
Step 5. log data and apply changes, rinse and repeat until you drive yourself crazy like I do. Hope this helps! Cheers

[Alirayshan]

reubone Thank you for everything what explained; but

Hello all;

Some values have been changed in the Borderline tables, while the MBT values remain the same. The values of Borderline 0-14 have been modified, as well as OP, but I have a reading of high values in a MP0. When copying its values in the histogram and taking it to MP0 table, making paste as subtract, the program does not accept these values, is there something wrong, or changing row axis values of vcm from load to MAP to be best??!!!

Note/ Why?re the values shown at 2.2 only??!!!

Q2/ what's the OP tables, does it copy values of Retard or Spark Advance of vcm and paste into OP table as subtract or what, in other words what does OP's table setup depend on (Reduce the error rate)?

Q3/ why in some Ford cars and in some their MP values of Borderline are higher than the MBT?!
Ford Explorer 20
Stock engine
Octane 85-87
Not use Dyno, just open road

Is there anyone who can turn the table for me professionally? I'm a colleague, as a beginner, all seniors and advanced tuner, it is up to you.............
mp00.jpgmp11.jpgmp22.jpgmp33.jpgmp44.jpg

Mod1.hpl
After Mod1.hpt

[mass-hole]

On my 2014 Ecoboost Ive never found 87 to knock the OAR down that far. Its usually on the good side of 0 whereas 91 octane will hang just shy of a -1 and 94(91 + Boostane will push to a -1)

Im pretty sure the OE settings are enough to allow for 85 octane with some safety margin. I've never tried but just based on how far the OAR drops from 91 to 87 indicated to me that it might end up just to the bad side of 0.

reubone Thank you for everything what explained; but

Hello all;

Some values have been changed in the Borderline tables, while the MBT values remain the same. The values of Borderline 0-14 have been modified, as well as OP, but I have a reading of high values in a MP0. When copying its values in the histogram and taking it to MP0 table, making paste as subtract, the program does not accept these values, is there something wrong, or changing row axis values of vcm from load to MAP to be best??!!!

Note/ Why?re the values shown at 2.2 only??!!!

Q2/ what's the OP tables, does it copy values of Retard or Spark Advance of vcm and paste into OP table as subtract or what, in other words what does OP's table setup depend on (Reduce the error rate)?

Q3/ why in some Ford cars and in some their MP values of Borderline are higher than the MBT?!
Ford Explorer 20
Stock engine
Octane 85-87
Not use Dyno, just open road

Is there anyone who can turn the table for me professionally? I'm a colleague, as a beginner, all seniors and advanced tuner, it is up to you.............
mp00.jpgmp11.jpgmp22.jpgmp33.jpgmp44.jpg

Mod1.hpl
After Mod1.hpt

Because at that specific air load it could run more timing than MBT without causing knock. They are Boarderline Knock tables. But you don't need to run more timing than MBT because that is where the most torque is made so the PCM will limit timing to MBT. As you increase air load, the octane will limit spark to less than MBT.

If you watch though, the Spark Source will become Baseline/MBT at light loads. At higher loads it will go to boarderline. If its cold enough and you have enough octane, the spark source will hit cylinder pressure limit.