Start tuning SR20DET

[Matt]

2022-07-01 15_33_36-Nistune [S14A(SR20DET) (Version_ 1)].png

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This point here is where it goes south. The MAF is still reading a voltage shwoing load (about 1.5V) whilst RPMs keep dropping below 800

What you see next is an increase in TP load (green) and injectoin time (orange)

Either put a bend between the turbo and the MAF (turbo probably still spinning and sucking through airflow, measuring load) to reduce the affects

Or update the firmware to FP1.1 or FP2.1 and use the antistall (TP limit table) so when TPS below the voltage in the table, we limit how far TP increases

[Skyline8075]

Do you think I can adjust anything else such as tpmin or something to fix? Just started to have this stall problem when I changed my cams. I feel like its a fueling problem with the cams giving it more air or maybe tps? The tps seems real erratic and i was really trying to baby as much as possible. I don’t even feel like boost had even started at these low rpms.

[Matt]

The TPS signal is slightly jittery. The only potential causes of that could be an issue with the 5V power/ground back to the ECU or the signal wire (assuming it is shielded all the way to the ECU). As usual start with the plugs/connectors and make sure secure and clean

If you hold it steady, the voltage should stay still on the TPS signal

Any extra airflow measure will result in more fueling, so that is something to consider, but we do see that MAF voltage hold quite high all the way through. Almost like turbo sucking airflow, or a leak

TPmax will limit injection time, but you can only really adjust it on the bottom end since it affects acceleration. That is why I added the 'anti stall' TP limit tables which get used when the throttle is under a certain voltage and then it stops TP cursor moving any further right

[kamilp1908]

And all working I have done with tunning the engine came to this result:

wykres200sx.jpg

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Boost is 1.25B (~18 psi)