High/low octane spark tables interpolation factor

[vsslpr]

Is there a parameter that can be read when logging which determines the weighting used for the spark interpolation from being weighted toward the high or low octane table?

[antus]

Which tune are you talking about?

[vsslpr]

The enhanced version of $51. Would it be similar for the other v6 na bins as well?

[VL400]

Its based on sustained knock retard. If you get lots of continual knock (as in over a long period of time) it will start to use more of the low octane table. It will slowly go back to using the high octane table if there has been no knock for a bit of time.

If there is a spare byte in the data stream The1 might be able to include the RAM item that shows how much of the low octane is being used?

[vsslpr]

Yep that's what I was trying to get an idea of, the actual weighting/percentage of either spark table value that is being blended to get the base spark advance.

I think it would help with tuning spark more "safely" coz you could just alter the high octane values roughly to begin with knowing you wouldn't cause any damage due to excessive knock. Then you could make changes to the high octane table based on the interpolation factors recorded at any given time?

[VX L67 Getrag]

The other thing to mention too, sometimes it can learn what the PCM detects as knock but can actually just be interference/noise, so that also needs to be correct!

[The1]

i have done a little testing on the bench with this and triggering knock, "Adaptive Spark" doesn't seem to be doing anything in stock form which is the code that sets transition from low to high spark tables, There is a 3D adaptive spark table that sets the starting CYLAIR value to try and transistion from low to high, i will have to look into this a bit more, also i think with knock learn this is only with Flash PCM's, but again have to look into this more as i can't remember since i last looked at the knock code to implement the KAL counter.

[vsslpr]

So if adaptive spark is the function that controls the transition between spark tables, and its been shown (on the bench at least) not to work then, which spark map would be read by default? They are both set to the same values in my current cal so it doesn't matter at present however the plan was to tune the timing by playing with those tables first. What input/information does adaptive spark use to determine transition to low/high octane tables? only knock detected?
Thanks for all the replies!

[The1]

from memory there is a timing degree window, so for the function to work you will want more than the timing in degrees specified between the two, there is a apply rate once there is no knock and cylair threshold is reached then it will scale the timing back up towards the high table at specified rate. I will have another look into this over the long weekend and report back as i intended to include a ADX value in enhanced to monitor hi/low status.

[VX L67 Getrag]

I've mentioned this a few times but not positive on it when I used to use kalmaker there was a variable that was logged & showed a 0% to 100% value that was logged that showed how much detonation was logged & the higher to 100% was when it ran on the low octane table, or opposite 0% was running on the hi octane table!

It was $A5 code & I'm 99% sure they didn't re-write coding for this it was just something that was natively there?