Tuning Boost Control With Bias Table
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Re: Tuning Boost Control With Bias Table
What did you learn. I'm still having issues getting it to work right. I get some long term oscillations, but more I just hits overboost.
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Re: Tuning Boost Control With Bias Table
I firstly had a slightly loose hose going to my solenoid that I fixed - So i required less duty to hit my targets. I tried setup mode, played with the duty % and it uses my bias table hitting my target perfectly, so to start I would suggest doing setup mode, enter duty number and see what %'s get you close to your target, like open loop pretty much (I did this last year setting all the gains to 0's before setup mode was created.)
Where I get lost is in basic mode the code is using duty numbers much, much higher than the ones on my table - why I'm not sure. In the picture attached the code kicks in at 43% duty - there isn't a 43% duty number on my bias table?
Where I get lost is in basic mode the code is using duty numbers much, much higher than the ones on my table - why I'm not sure. In the picture attached the code kicks in at 43% duty - there isn't a 43% duty number on my bias table?
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Re: Tuning Boost Control With Bias Table
Ok, so looking at nathaninwa's thread with the same "issues" I think I've found my cause for mine. I'm going to test and report back.
edit: no dice, I made my target table all one value and still hit overboost. going to try adjusting frequency next.
edit: no dice, I made my target table all one value and still hit overboost. going to try adjusting frequency next.
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Re: Tuning Boost Control With Bias Table
How are you doing boost. Just one table or blended? I found with gear based blending the code is goofy along with gear switching. I'm able to run single boost level or the boost by gear on the main boost page with great success.
At the track I was able to nail my targets in setup mode with only about 5kpa oscillation. I then turned basic mode on and with the slider at 1/4 only my targets were met.
At the track I was able to nail my targets in setup mode with only about 5kpa oscillation. I then turned basic mode on and with the slider at 1/4 only my targets were met.
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
Re: Tuning Boost Control With Bias Table
This is as close as I could get it today.
What would you suggest changing?
What would you suggest changing?
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Re: Tuning Boost Control With Bias Table
I have two target tables, based on ethanol %. At the moment I'm using only one as I have yet to get some e85 in the tank and tune it.nathaninwa wrote:How are you doing boost. Just one table or blended? I found with gear based blending the code is goofy along with gear switching. I'm able to run single boost level or the boost by gear on the main boost page with great success.
At the track I was able to nail my targets in setup mode with only about 5kpa oscillation. I then turned basic mode on and with the slider at 1/4 only my targets were met.
Do you know if the slider is active in setup mode? At the moment it's the only thing that works for me even when I set the slider to zero in basic mode it's automatic overboost. If Ken or someone could explain the differences between the release code boost control and this so I can understand it would be a good start, this new system has potential to be fast reacting when dialled in.
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Re: Tuning Boost Control With Bias Table
You must have a current msq posted. I'll check it out tomorrow
In a nut shell, release code uses and initial value, then bases the rest of the duty cycle on pid alogorythms and not really having a reset point
The current beta stuff I like to think of it as a ve table of sorts. We tune for an afr (boost duty) open loop style then once were close we turn on O2 correction ( slider and pid) to maintain and correct for day to day changes. Since the code is using the bias table it always has a new reference to base boost duty on so the code doesn't have to work so hard
Setup should be just that. Setup mode ran open loop only
As with my case, turn any boost blending off and use a single target table only to not have the ethanol table a possible problem like I found.
In a nut shell, release code uses and initial value, then bases the rest of the duty cycle on pid alogorythms and not really having a reset point
The current beta stuff I like to think of it as a ve table of sorts. We tune for an afr (boost duty) open loop style then once were close we turn on O2 correction ( slider and pid) to maintain and correct for day to day changes. Since the code is using the bias table it always has a new reference to base boost duty on so the code doesn't have to work so hard
Setup should be just that. Setup mode ran open loop only
As with my case, turn any boost blending off and use a single target table only to not have the ethanol table a possible problem like I found.
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
Nathan did you ever post logs/msq of the blending problem?
Megasquirt is not for use on pollution controlled vehicles. Any advice I give is for off road use only.
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Re: Tuning Boost Control With Bias Table
I did Ken, in the 1.4.10 boost thread we were posting in
Boost by gear on the main boost page is working great and allows me to tune each gear in a single pass
Boost by gear on the main boost page is working great and allows me to tune each gear in a single pass
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
I understand, the bias table is to get close your target so then pid can do its thing. Does it function the exact same as the old named "initial duty table"?
Here is my msq:
Here is my msq:
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Re: Tuning Boost Control With Bias Table
I look at your msq when I get home. The bias table is load specific and rpm dependent. I'm finding for most installs after peak tq the dc needs increased. And the code will use what you put in the table, so if it's over boosting in setup mode the the dc is to high.
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
If I was testing your car. I would disable the blend table and tune boost table 1 only right now. I would also add some resolution to the bias table by rescaling where boost actually starts, meaning rather than a 1500 rpm bin it might start off with a 2500 or 3000 bin
I know your in setup mode, but move the slider to zero and data log that
Is the turbo small for the application?
I know your in setup mode, but move the slider to zero and data log that
Is the turbo small for the application?
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
Good call on fixing the axis, I now have it from 2500rpm up.
I have a Comp turbo 6465 turbo on a 3.0L inline 6, T3 manifold.
On the older code I had no issues w/boost control, even on the dyno it was great, change the desired boost target and MS would hit it.
Going to try basic mode with slider low, I turned off blending for now so there are no "distractions" haha
I have a Comp turbo 6465 turbo on a 3.0L inline 6, T3 manifold.
On the older code I had no issues w/boost control, even on the dyno it was great, change the desired boost target and MS would hit it.
Going to try basic mode with slider low, I turned off blending for now so there are no "distractions" haha
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Re: Tuning Boost Control With Bias Table
Your setup just about the same as mine. 3.0L with a precision 6466
Post a log with blending undone. Your bias table seems backwards to me then. I roll into boost say 30dc and come out the top at 35dc to flatline boost. Yours is high and tapers low which might be causing a false overboost
Post a log with blending undone. Your bias table seems backwards to me then. I roll into boost say 30dc and come out the top at 35dc to flatline boost. Yours is high and tapers low which might be causing a false overboost
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
My reason for tapering is I have a pretty free-flowing exhaust, cams etc and when i keep DC the same or higher uptop boost rises. Say if I punch it at 5-6k i would tend to hit overboost protection with higher DC% since the turbo lights up really quickly.
I have a log with basic mode, slider to 0 and again this makes no sense. see first photo. will also attach log.
why does it go to 49% and totally ignore my bias table? and then ridiculously ramp up DC%?? see record 6177 in log.
I then turned switched back to setup mode with no other changes, and you can see the difference in behavior. Second pic. see record 10240 in log
here is the log:
https://drive.google.com/file/d/0B3GWeG ... sp=sharing
I have a log with basic mode, slider to 0 and again this makes no sense. see first photo. will also attach log.
why does it go to 49% and totally ignore my bias table? and then ridiculously ramp up DC%?? see record 6177 in log.
I then turned switched back to setup mode with no other changes, and you can see the difference in behavior. Second pic. see record 10240 in log
here is the log:
https://drive.google.com/file/d/0B3GWeG ... sp=sharing
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Re: Tuning Boost Control With Bias Table
anybody?? I dont want to go back to the release code but I just might to regain my boost control!
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Re: Tuning Boost Control With Bias Table
Let me charge my laptop up and i take a look
Volvo 940, 2jzge, MS3Pro, daily
240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
That last tune you posted you said you made the boost blending changes so its just a single target? And in that last msq what is up with the boost control pin setup to off?
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240Z, 2JZ, MS3Pro boost control
240Z, 2JZ, MS3Pro boost control
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Re: Tuning Boost Control With Bias Table
Yeah, just one target with blending off. That's strange it's off it was surely on previously. I've turned back on boost blending as I filled up on some winter blend e85 from NY so I'm setting that up. I can post my latest msq shortly. Appreciate the help nathaninwa!
edit: here is my lastest msq
edit: here is my lastest msq
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Re: Tuning Boost Control With Bias Table
going back to the last release when my boost control was working to see if something is up with my setup or a firmware difference.
nvm, gonna try changing the frequency for 26 to 39 (using a 3port mac valve)
nvm, gonna try changing the frequency for 26 to 39 (using a 3port mac valve)