HI Knock counts on Vt 304 engine running 11P

[sparx-1]

VL400 wrote:
Lets say you are logging at 10Hz, or 100ms between logging frames. Knock counts are a delta count over a 12.5ms period, so with 100ms gaps between logging frames there are 8 delta count calculations which you missed 7 of. If only one of those 8 had some delta counts (which would then produce some knock retard), logging only around 1/8th of the calculations there is a pretty high chance of that one delta count calc being missed

Looking back through some of my logs the logging speed in tuner pro is on 3.3Hz most of the time. im sure it used to read around 10Hz while logging. If my connection speed is this slow that means if i was watching knock counts i wouldnt see much But i would see the result of timing being removed on the knock retard value before any knock counts happen

Red: RPM
Blue: Knock Counts. 238 equales no knock, Drops to 92 when knock counted
Green: Knock Retard Value

[Yortt]

VL400 wrote:
Lets say you are logging at 10Hz, or 100ms between logging frames. Knock counts are a delta count over a 12.5ms period, so with 100ms gaps between logging frames there are 8 delta count calculations which you missed 7 of. If only one of those 8 had some delta counts (which would then produce some knock retard), logging only around 1/8th of the calculations there is a pretty high chance of that one delta count calc being missed

Looking back through some of my logs the logging speed in tuner pro is on 3.3Hz most of the time. im sure it used to read around 10Hz while logging. If my connection speed is this slow that means if i was watching knock counts i wouldnt see much But i would see the result of timing being removed on the knock retard value before any knock counts happen

Red: RPM
Blue: Knock Counts. 238 equales no knock, Drops to 92 when knock counted
Green: Knock Retard Value

This appears to be showing knock retard is being logged before knock counts this is confusing given "There cannot be knock retard with no counts" or as this post points out it is caused by missing the knock count that generated the knock retard because of the slow logging speed if this happened then the knock counts should have already reduced and be shown at the knock retard point, assuming the logged packet is receiving all pids at the same time (unlike the LS1 logging). It would be interesting to see the result at 10fps and 30fps.

[VL400]

this from memory is correct as I was using message 6 ADX at that time.

Ahh this makes more sense, using message 6 then that is correct. But, being message 6 its a user configurable custom message. You get to choose what you log and how many items you log. Can add knock retard to the message in place of counts if you want, or add it as a new item.

Isn't this the same as removing 1.99deg of timing at the rpm and load point in the timing map as indicated by knock retard

So my question is, how do you know it needs 1.99deg removed at that point? Changing the attack rate changes the amount of timing removed for the same counts.

Good to have this ability but the big question how to you determine harmonics are the cause of knock.

By tuning to MBT with knock retard turned off (you can still see counts). If you are getting knock counts and taking out some advance does not remove the counts then its likely false knock. They can then be masked by the ignore counts table, but you need to know the counts to set this table up.

if logging knock counts improve the ability to determine the optimum knock threshold I would like to understand how, strickly from a tuners point of view.

I dont really tune by the knock sensor on these early ECUs. But I tend tune effect based on cause. Trying to tune effect without knowing the cause would be like trying to tune AE and not worrying about TPS/MAP, just what the wideband shows. As knock attack is the configurable effect to the cause of knock counts, for my way of tuning to get the desired result I need to consider the counts. This is just my method, and by no means is the only way to skin this cat.

Looking back through some of my logs the logging speed in tuner pro is on 3.3Hz most of the time. im sure it used to read around 10Hz while logging. If my connection speed is this slow that means if i was watching knock counts i wouldnt see much But i would see the result of timing being removed on the knock retard value before any knock counts happen

Wow something is not right with that. The included ADXs log both engine and trans, TunerPro does not show the total throughput of all frames so you should still see 8-10Hz. 3Hz might need to tweak the ADX a bit adding a bit more delay between frames. The default value of "small listen for silence" is 5ms, try with 10 or 20ms.

In regards to the log screenshot. It is the way the data is being interpreted, TunerpPro is drawing lines between engine data points. When logging two messages (engine and trans) data does not exist all the way along the line. The point marked in the log would have been when a trans message was returned. As this does not include the engine params, TunerPro draws a line between known engine data points, but in the process appears to create data. There was no knock retard at that point in time.

[sparx-1]

The average logging speed is around 10Hz while recording but when i play back the log. pause it and jump forward samples using ] short cut key on the keyboard and look at the Hz reading its around 3Hz logging speed is this normal because it is recording all data.
I will try tweaking the adx and see if that works

[Holden202T]

I normally see 15hz recording speed and up to 30hz with message 6 logging.

[sparx-1]

I normally see 15hz recording speed and up to 30hz with message 6 logging.

Nice Im using 11p, Is Message 6 Logging the same as Messagge 11 in 11P?
Time to do some more reading and get my head around how to set it up properly as it only has knock counts and i defenitily need Knock Retard Value logged as well.

When you slow down your recorded log and play it back at a playback speed of say 25%will it still show the same as your recording speed 30Hz?

[Holden202T]

oh .... message 6 I have only done with $12P not $11P sorry ....

as for playback speed, that's just how fast the view moves, it doesn't change what it shows, that determined by the data you get while recording .... and sometime computer performance can dictate how fast you can play it back.

[sparx-1]

Oh ok i see now if i play the log at 400% speed it shows 40Hz if only i could log at that
Thanks

[VL400]

Im using 11p, Is Message 6 Logging the same as Messagge 11 in 11P?
Time to do some more reading and get my head around how to set it up properly as it only has knock counts and i defenitily need Knock Retard Value logged as well.

When you slow down your recorded log and play it back at a playback speed of say 25%will it still show the same as your recording speed 30Hz?

Yep message 11 in 11P is the custom configured message. Logging both the retard and counts is the go With a small message and the ALDL logger 40hz is possible. My normal tuning message that is a 24 byte message 11 plus analog is 21hz.

Playback speed is PC speed dependent, the monitor view needs more processing so tends to be slower than all other views.

[Holden202T]

also keep in mind when your recording a log, if you have for example the dash screen showing that can slow down the speed that the computer can take it all in!