Bias lag filter PID.
Is there such a way that we could get a PID for the bias lag filter? I think that being able to log that would help in being able to determine how/when it affects bias temperature blending.
Bias lag filter PID.
Is there such a way that we could get a PID for the bias lag filter? I think that being able to log that would help in being able to determine how/when it affects bias temperature blending.
I agree.Originally Posted by LinearX
I have the following Calculated PID working pretty good as referenced in another thread. http://forum.efilive.com/showthread.php?t=12848&page=15.
CALC.VE_BLEND = {SAE.MAF.gps}*({SAE.IAT.C}+(({SAE.ECT}-{SAE.IAT})*{CALC.BLEND})+273.15)/((displacement()*61.024)*{SAE.RPM}*{SAE.MAP.kPa})* 212544
If we are talking about Table B4902 Charge Temperature Filter, that would be nice. Can you do it through just using the lookup table parameters, or is it more difficult than that?
LinearX, are we talking about the same filter?
Shawn, I am, indeed, referring to B4902.
Last edited by LinearX; February 17th, 2010 at 02:46 AM.
I heard it could be a tough one to get as a DMA PID.
Joecar gave me a possible explanation.
Paraphrased..
[B4902 is the ramp-in rate applied to the blended temp (or rather the rate at which the blended temp is applied to B0101)...
I.E. if the blended temp is T1 and then has to change to T2 (due to either ECT or IAT changing), B4902 is the rate at which the blended temp changes from T1 to T2...
...the time taken for blended temp to go from T1 to T2 would be something like B4902/(T2-T1) or B4902*(T2-T1)...
...the units (factor) of B4902 don't give us any clues... it could be K/s or s/K... the units would be a big clue...]
Other than a PID, one way to work around it would be filter out rapid IAT changes. Probably not the answer you are looking for, but at least a 'work-around' B4902.
It would at least minimize its effect..
Shawn, you're overthinking this. Start with the simple case: you know MAT is correct, just solve for GMVE. That's relatively simple. Only when you understand that in and out, you wanna venture out into the dangerous land of bias and lag.
Your right.
What is MAT?
What is GM.DYNAIRTMP_DMA actually describing?
No description exists (done searches). One thing I can promise you is I am going to stay out of the temperature biases and lag world. It borders on impossible.
Problem is I need a 'charge temperature equivalent' (none for my OS).
MAT as in Manifold Aircharge Temperature. It's the final temperature estimator value, after all the bias/lag stuff is done and over with. It's available on some platforms, because I've been doing experiments, and Ross/Paul been kind enough to help me out.
O.K. that was helpful.
That has not reached the masses yet.
I just upgraded to the latest beta version of the software, and the GM.DYNAIRTMEP_DMA PID became available on the 12212156 OS for a Chevy Silverado and OS 12221588 for my 2002 Corvette.
If you're running either of those OSes, MAT may be available to you should up upgrade.
Thanks LinearX.
I have the GM.DYNAIRTMP_DMA. Do you know exactly how it is computed? I did a log yesterday.
For example:
ECT: 95C,
IAT: -8C,
GM.DYNAIRTMP was 14.9C,
Blending Factor was .024.
It ranged from 0.0C to 52C..
I have done search. There is no Pid description. Is it telling me the blending temp? Do you know?
Thanks for the heads up. It is not always easy to find some of the Pid descriptions.
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