Static/Dynamic compression ratio.

[slo-svt]

What criteria are you having the issue (what manifold pressure rpm). I don't see anywhere in the log where it ever goes into pe with the flag or your wideband readings. If that MAP reading is in kpa i personally like to see them go into pe around 80kpa. If you had a key that would say was all the acronyms on headings are I am sure i could be more help but my personal opinion is when loading it (97kpa map at 1500rpms) I would get the actual afr to something like 13-13.5 and see if that helps.

[Newold1]

It's all in the tune! Almost nothing in the mechanicals or dimensions leads me to believe there is anything that needs major correction other than the TUNE!

[dfarr67]

Supplied SA tables.

[dfarr67]

Working on.

[slo-svt]

What criteria are you having the issue (what manifold pressure rpm). I don't see anywhere in the log where it ever goes into pe with the flag or your wideband readings. If that MAP reading is in kpa i personally like to see them go into pe around 80kpa. If you had a key that would say was all the acronyms on headings are I am sure i could be more help but my personal opinion is when loading it (97kpa map at 1500rpms) I would get the actual afr to something like 13-13.5 and see if that helps.

Seems like maybe this was too vague so I will break it down some
Where is this happening? You originally said lingering ping but didn't mention the conditions that cause it to ping (what rpm, load, ect)
1. Is the MAP reading in kpa? If so why does it only read 90 at key on engine off at the end ?( do you live on a mountain or is it described incorrectly in computer)
2. Does knkct stand for knock count? Is the engine equipped with knock sensors ? If so what unit are they measuring in?
Im still thinking a fueling issue.
I am still thinking fueling. Maybe as a test force open loop and increase the high map areas (85kpa and above) of ve table by 10 percent and see if condition is improved. This could also be acomplished by increasing pe at <3000rpms to something leaner say (13-13.5) then decreasing the tps pe enable value to whatever your hitting when it acts up.
4. what kind of wideband are you using and where is it located? Only reason I ask is when you see the o2 dip in your log the wideband stays dead steady.

[dfarr67]

These are some knock maps before I went back to premium.
- Knock was occurring under moderate to heavy throttle, I didn't want to really push things.
- Yes reading is in Kpa.
- You can see the selected display as total counts.
- GM oe style knock sensor with replacement oe (less sensitive ESC module) and 90 deg elbow to desensitize knock sensor.
- WB is Spartan2 with Bosch 4.9 located aft Y in front of cat. clocked probperly. https://www.14point7.com/products/spart ... ntroller-2
- altitude of 925 metres (3,035 ft).
- Would have to note typical noisey gm roller lifters, roller rockers, headers- you know all the good stuf hitting on poor knock sensor (resonant type). Pistons a little loose until hot.

Hope this helps.

[slo-svt]

So is the engine noisy around 3500? Seems odd to me knock would be worst as your getting up in the rpms. Are you hearing it or just seeing it on the log?

[dfarr67]

On those earlier tunes- I could hear the ping. And I agree that it may have a lot of factors but running lean may be the biggest one. The truck was very strong in non knock areas.