I am trying to gain a better understanding of how spark advance is calculated in ford falcons and I do not seem to be able to get my calculations to match what I am receiving via the scanner. If anyone is able to shed some light on this topic or notices anything wrong then please do correct me. I assume that load is calculated based on map ( map/101 in kpa.) and all axis in the tables are the same as the sensor readings from the scanner. As I do not have expected lambda I base the lambda off the lambda lookup table values. I am certain that more corrections for lambda are present and this is not exactly what is demanded but I would expect it is in the ball park for most operating conditions as long as nothing is too far from the norm, no sharp jabs of the throttle ,no engine or cat protection doing its tricks etc. I am also aware that the obd2 port may not be the quickest to have exact matches as the speed of obd2 port can provide a little lag between each reading.
Is timing calculated using:
Borderline knock + base lambda correction + (IAT spark base*IAT spark multi) + (ECT spark base*ECT spark multi) + (IMRC spark base*IMRC spark multi) + VCT Correction + emissions retard - knock retard - torque reductions- other factors + other factors =total timing.
Is this correct??
Timing will be removed or added back if knock is present or has been present very recently, again if torque reduction is present, I am also guessing if cat protection or engine protection is also present, also probable other factors I am not aware of then timing will be removed. I am also assuming that MBT is used only in the torque modelling and is used to show how much torque is missing based on how far spark advance is from MBT figure and how much timing to remove or add to achieve the torque change required.
Is open loop a factor in timing calculations? Is there more factors and influences I am missing or possible tables.
I just realised I am not able to upload the spreadsheet as it is nearly 2mb in size. I will have to look at another way to make it available so see if anyone can see any errors.