iat based antilag / retard, iat adv only sometimes kicks in
long story short. gen 1 e67 stick shift. MAF tune.
Relay is activated when clutch is pressed to set -40 iat. The relay works 100% of the time, and sets -40 IAT. However the timing retard only intermittently works, or im not fully understanding how its triggering.
For example, iat will get triggered to -40, sometimes iat advance shows the -15 deg i baked in, and timing is sucessfully pulled. Other times, iat advance shows 0 and no timing is pulled.
Same tune, 2x datalogs. One data log it works, the other it doesn't.
So it looks like the IAT tables i showed earlier trigger on the MAT versus IAT value. You can see where in one datalog where MAT temp goes negative (what we want), and the other the MAT has no change, and no timing is pulled on the bad datalog.
I changed Cyl charge bias and filter to 0 and 1 respectively which *should* best mimic the actual IAT value and ignore baking in the ECT temps into the MAT calculation.
But MAT temps are doing whatever they want. I have no control. This car has no IAT2 from factory, but i changed that all to -40 for fun, no help either. I'll attach the tune if anyone knows whats going on here.
Last edited by itsdaveonline; 04-18-2020 at 05:35 PM.
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