Boost PID=200,0,0 - still hits boost limit
08-23-2013, 01:29 PM
#22
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According to Megasquirt MS3 Loading Firmware:
So it appears that the change was made before the current version I am using. It appears I should stick with normal.
1.2.x firmware
Boost Control : a few critical settings have changed
To make things more intuitive we have now changed the firmware so that
- "Normal" is the most typical output polarity setting
- larger boost duty% numbers mean more boost.
If you are a new user starting out from scratch using 1.2, then nothing needs to be changed, just use the default settings.
If you are upgrading from a previous firmware version, then the Boost Output polarity setting will be the opposite. For most users it will now be "Normal". This is true whether using open- or closed-loop boost control.
If you're using closed-loop, nothing else should need to change. Open loop boost users most likely need to set their table so that:
new_cell_value = 100 - old_cell_value
Remembering that more duty = more boost.
Boost Control : a few critical settings have changed
To make things more intuitive we have now changed the firmware so that
- "Normal" is the most typical output polarity setting
- larger boost duty% numbers mean more boost.
If you are a new user starting out from scratch using 1.2, then nothing needs to be changed, just use the default settings.
If you are upgrading from a previous firmware version, then the Boost Output polarity setting will be the opposite. For most users it will now be "Normal". This is true whether using open- or closed-loop boost control.
If you're using closed-loop, nothing else should need to change. Open loop boost users most likely need to set their table so that:
new_cell_value = 100 - old_cell_value
Remembering that more duty = more boost.
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08-24-2013, 07:15 AM
#25
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By initial overshoot what rpm are you referring to? In order to get any overshoot I had to lower my P to something like 7, and then it was at about 4,200rpm.
To be honest, I am a bit lazy about it right now. I am at something near my original numbers at 20:22:100 right now and it feels a lot better than it has been while trying to find P, and frankly I have been just messing with it while driving to see what seems to be better by watching boost gauge on dash. Looking at a quick log, I am back to a situation where I am not hitting/overshooting target until higher RPMs and then in an oscillating fashion. But it feels good and seems safe so I am not too concerned at the moment.
Sunday I am off of work and I will start doing some tuning while watching my logs and we will see how it progresses.
EDIT TO ADD:
Reading some more it looks like some of what I was doing was wrong, some of the time. I thought for some reason that tuning P had to be done in a low gear rom 2,000rpm up. That doesn't really result in a super rapid increase in pressure compared to say, starting at 4,000 rpm in second. I THINK I will end up about where I am at with a starting P of 7, but I will re-test a bit tonight and tomorrow.
To be honest, I am a bit lazy about it right now. I am at something near my original numbers at 20:22:100 right now and it feels a lot better than it has been while trying to find P, and frankly I have been just messing with it while driving to see what seems to be better by watching boost gauge on dash. Looking at a quick log, I am back to a situation where I am not hitting/overshooting target until higher RPMs and then in an oscillating fashion. But it feels good and seems safe so I am not too concerned at the moment.
Sunday I am off of work and I will start doing some tuning while watching my logs and we will see how it progresses.
EDIT TO ADD:
Reading some more it looks like some of what I was doing was wrong, some of the time. I thought for some reason that tuning P had to be done in a low gear rom 2,000rpm up. That doesn't really result in a super rapid increase in pressure compared to say, starting at 4,000 rpm in second. I THINK I will end up about where I am at with a starting P of 7, but I will re-test a bit tonight and tomorrow.
Last edited by Chiburbian; 08-24-2013 at 04:08 PM.
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08-26-2013, 06:38 AM
#26
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Here is where I am at as of about 5am today.
I overshoot almost to 185kpa and then settle near target. I am thinking that means I should up D some?
Overall, pretty good.
Virtual Dyno tells me it is about 189hp and climbing. I didn't even go to redline.
Still some tuning to do obviously but pretty happy with it at this moment.
EDIT:
Superimposing my old pull on this one tells me that I am actually making LESS power. Mind you that was a 5th gear pull and this was a 4th gear pull but still. Surprised. Either way it feels pretty good.
I overshoot almost to 185kpa and then settle near target. I am thinking that means I should up D some?
Overall, pretty good.
Virtual Dyno tells me it is about 189hp and climbing. I didn't even go to redline.
Still some tuning to do obviously but pretty happy with it at this moment.
EDIT:
Superimposing my old pull on this one tells me that I am actually making LESS power. Mind you that was a 5th gear pull and this was a 4th gear pull but still. Surprised. Either way it feels pretty good.
Last edited by Chiburbian; 08-26-2013 at 06:52 AM.
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08-26-2013, 09:54 AM
#27
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What PIDs on this last one? Looks like to little P - add P of 1 or 2 and try again...
Also - I would set the Boost lower limit delta more to something like 40 or 50 because that keeps the valve shut for a
longer time - so boost can rise faster...
Also - I would set the Boost lower limit delta more to something like 40 or 50 because that keeps the valve shut for a
longer time - so boost can rise faster...
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08-30-2013, 02:32 AM
#28
Reading the end of this page: Megasquirt MS3 Loading Firmware clears up some confusion over the correct output polarity for the OP's valve compared to the correct output polarity with ms2 release or older ms3 1.1.x codes.
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09-06-2013, 11:08 AM
#29
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Here is where I am at today. I started over and ended up pretty much where I was before.
Back on 8/26 I was at 8:5:60
Today I am at 10:5:0 (not tuning D until I get a few things worked out). Target is 172kpa.
I am not terribly upset with how I am holding boost to redline as you will see in the following graphs, but it does seem that I am getting some oscillation as I go up in RPMs. Also, in lower gear pulls I barely ever touch my targets. Heavy oscillation. I don't have any logs of that though.
What I AM seeing however is heavy overboost when I do a full throttle pull in higher gears. For example, the log/graph below is a pull in 6th gear.
What should be my next step? What should I try?
Back on 8/26 I was at 8:5:60
Today I am at 10:5:0 (not tuning D until I get a few things worked out). Target is 172kpa.
I am not terribly upset with how I am holding boost to redline as you will see in the following graphs, but it does seem that I am getting some oscillation as I go up in RPMs. Also, in lower gear pulls I barely ever touch my targets. Heavy oscillation. I don't have any logs of that though.
What I AM seeing however is heavy overboost when I do a full throttle pull in higher gears. For example, the log/graph below is a pull in 6th gear.
What should be my next step? What should I try?
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