Spark vs IAT table not correlating with actual IATs

[GMCtrk]

I'm prepping to do the AutoVE thing and get the wideband in, so I set up my tune as SD, failed the MAF. I am only getting like 9-12.5 degrees of timing at WOT and if you go to the high octane spark table its supposed to be like 23. If you open up the spark IAT table with the log file open it's highlighting the 50-55 degrees Celsius whereas the log is showing actual IATs of 12-15 degrees Celcius. Even then though the IATtable pulls like 5 so I dont know where else its pulling from.

[WeathermanShawn]

I think your units in your tune (C) or (F) and log both need to be in metric or imperial to display properly. I usually just keep the display units in metric for both tune and scan to see tables read the same units.

As far as why your spark is dropping so much? You are probably best logging every Spark PID possible. Sometimes it can be Spark Retard from the Air Conditioner, Traction Control, EGR, Fuel Mixture Spark Correction etc. I am only familiar with the M-6, so I do not know if your transmission settings affect spark.

What were your actual IAT(s) and were you running AC?

[joecar]

Make sure you selected the same units in the scantool (set on PIDs tab, view on Data tab) for the pid(s) mentioned on the table axes in the tunetool.

[dc_justin]

Couple of things here:

With VE table values as high as you are seeing, your air mass per cylinder is going to be a lot higher than it was with the MAF enabled... eg, .95 instead of .83. That will push you farther over in the spark table.

You're not logging the correct air mass per cylinder PID (I would suggest never using calc.cylair for spark reference). You need to log one of the DMA PIDs or GM.DYNCYLAIR for air mass reference in speed density. CALC.CYLAIR is derived from the MAF, so as you are changing your VE table values, it is not being reflected in your log file.

[GMCtrk]

Justin was correct. The stock 6.0 tune has spark values of like 8-12 degrees with .84 grams/cyl and up.

Anyways, so just for anyone interested, today was the first time I went WOT several times and got no knock. Apparently the root of my problem were the knock sensor sensitivities on the stock 6.0 tune. They are set very sensitive and they must not like my aftermarket springs and pushrods. A 6.0 up top has a sensitivity of .95 whereas a 4.8/5.3 is set to 1.30!

Now the issue I have is that my timing table doesn't perfectly correlate with what I'm actually getting. I am indeed logging GM.DYNCYLAIR. E.G. up top I command 24 degrees and actually get like 25.5, 26, 23.5, etc.

Also, my engine runs leaner in 3rd gear WOT than 2nd gear. Is this normal? And also, how much of a discrepancy between the bank 1 and bank 2 O2 sensor readings at WOT should there be?

THANKS!

[GMCtrk]

I was doing some searching on here and it looks like I really wasnt running in true SD. It looks like in order to fully disable the MAF I also have to set the Engine DTC processing enablers Po101-103 to C:Non Emissions. Can anyone confirm this? In the AutoVE tutorial it has one unplugging the MAF, but on the truck MAF it has the IAT sensor incorporated so I left it plugged in. I'm thinking if the MAF was still operating that's what could be throwing off my timing.