I was going to start a new thread but might as well post it here. i have been looking at why I am getting KR when i initially go WOT? I have all burst knock tables disabled, could this be false knock? This is the worse case of it I have seen. Normally i only get one degree.
Do you hear anything on initial tip in...?
Are motor mounts torquing/bumping/limiting...?
Is oil pooling inside intake manifold...?
Do you see KR when IAT and ECT are cooler...?
Commanded EQR is 1.28... could this be causing rich knock...?
What fuel are you running...?
Hmmm, commanded AFR and wideband AFR are different.
Could the difference in commanded AFR and measured AFR be commanding the incorrect stoich AFR for the fuel being used? Or the wideband not being programmed for the correct stoich? Just trying to think of other possibilities besides an incorrect MAF or VE table...
In my experience 25* timing is more advance than I can run without knock at that rpm and g/cyl. Not sure which engine you have, but I'm commanding around 20-21* under those conditions to avoid knock. I would think if you pulled back the timing there it might help spool your turbo a little quicker as well
14 GMC Sierra
5.3L CC SB 4x4
Basic tuning....
I am running on e85. the commanded afr is shown on the 85 scale, but the wide band is show on a gas scale. (because i'm use to using gas scale when tuning)
This is an ls1 with front mount turbo kit.
Discrepancies in stoich AFR in tune and wideband...? Maybe if they are different... but if they are the same then both commanded and measured AFR would be that stoich AFR in Closed Loop... (if you use Lambda you will see 1.00 in Closed Loop). It seems to me that both your VE and MAF are not correct.Originally Posted by Wheelz
GenIII engine typically takes no more than 24* timing at peak torque, and sometimes less depending on fuel.
I am still dialing in the VE table. It is pretty rich and I'm slowly leaning it out to get it dialed in 100%, but i have no maf.
I'm thinking I simply am commanding too much timing. I will back it off in that area and see what happens.
Hmm could be rich knock from too much fuel before boost. I had knock going at that EQR that cleared up when I went to 1.17 EQR. Not sure though.
14 GMC Sierra
5.3L CC SB 4x4
Basic tuning....
For E85 do this:
- set your B3601 to 9.7.
- make sure that your injector duty cycle does not max out (or rather stays below 80% or 90%).
- set your calc_pids.txt to use EQR and/or lambda for commanded fueling and wideband measurement.
- get VE and MAF tables corrected so BEN for both is close to 1.00.
- recheck injector duty cycles,
- check LTFT's.
Note:
you should use a BEN pid based on lambda and/or EQR...
examples:
if you have FlashScan V2 with serial wideband connection:
your BEN will be "{GM.EQIVRATIO}*{EXT.WO2LAM1}"
if you have FlashScan V1 or V2 with analog wideband connection:
you BEN should be "GM.EQIVRATIO}*{CALC.AFR_xxxx}/14.7"
(where the 14.7 should actually be the default stoich AFR of your wideband).
I was trying to say it looks like they could be programmed differently, didn't do a very good job of that.
14 GMC Sierra
5.3L CC SB 4x4
Basic tuning....
With boost, EQR 1.28 is ok, should not be causing rich knock (rich knock does not usually happen, it can, but not usually, forget that I mentioned it).
but check injector duty cycle, if it hits 100% then you would be going lean and you might be getting lean knock...
but I see your injector duty cycle is still below 100%...
but see what the injector duty cycle is when MAF and VE are corrected (BEN stays very close to 1.00 all the time).
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