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Old 04-18-2016, 05:46 PM   #21
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Start with a 20kpa delta. Once your tuning gets good you can lower it. The delta is basically just a holdoff that keeps the wastegate closed until you are close to your target.

Theoretically you don't need those rows of 100, because the algorithm will be keeping it closed anyways. I use those rows to get more resolution in my rpm.
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Old 04-18-2016, 05:49 PM   #22
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Start with a 20kpa delta. Once your tuning gets good you can lower it. The delta is basically just a holdoff that keeps the wastegate closed until you are close to your target.

Theoretically you don't need those rows of 100, because the algorithm will be keeping it closed anyways. I use those rows to get more resolution in my rpm.
Where do you set the delta? I see no option for that.
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Old 04-18-2016, 05:51 PM   #23
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Originally Posted by Help bubble
(Closed-loop) Boost pressure must be within this many kPa of the target boost before closed-loop control will activate.

Outside of this range the valve is held wide open (keeping the wastegate shut) for fastest spooling.
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Old 04-18-2016, 05:57 PM   #24
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Oh, wow, OK, that is set to 100, so it currently only holds the wastegate closed until I am within 100 kpa of the target!? Ok, I didn't understand that setting at all, wow. I thought that was just setting the whole table to see 100kps as atmospheric, good grief. OK, 20% sounds much better, now that I understand it. How close (small) can you get that delta without having boost spikes, I wonder?
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Old 04-18-2016, 05:58 PM   #25
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Depends a lot on your setup and tuning. As I said before, mine is set to 20kpa (not %, stop saying percent). I also have a really fucky wastegate and boost control is very hard. My bias table looks ridiculous.
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Old 04-18-2016, 06:05 PM   #26
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Yes, 20kpa, not %, sorry. I set it to 20kpa just now. I think I've got this map ready to test, but I need my driver, I can get so much more done when I have someone to drive and do what I tell them instead of datalogging and pulling over all over town. Trying to get him to come and drive this afternoon so I can try this.
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Old 04-18-2016, 09:18 PM   #27
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Ok, that was disappointing, I went from having a tune that was hitting really solid boost when tuning it wrong, to one that doesn't hit the targets anymore, and has also developed way more oscillation in the boost. I tried lowering the duty numbers a little and raising them a little, but that didn't help. Raising the delta to 30 kpa seemed to diminish the oscillations a little, but it's really rough. When I look at the log file, it doesn't make much sense to me, it never really meets the targets, and takes a long time to get close. Any chance you could look at the log and tell me what you think I'm doing wrong?
Attached Files
File Type: msq CurrentTune.msq (242.9 KB, 30 views)
File Type: msl 2016-04-18_16.53.29.msl (715.7 KB, 41 views)
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Old 04-18-2016, 09:40 PM   #28
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Well you brought your duty table down a bunch. It went from 30 to 23? It worked before? Why did you change it.

Never mind. Your 190kpa looks the same. I'll look tonight.
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Old 04-18-2016, 10:02 PM   #29
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Well you brought your duty table down a bunch. It went from 30 to 23? It worked before? Why did you change it.

Never mind. Your 190kpa looks the same. I'll look tonight.
Ok, I notice in the log, that the boost duty never went below 33 through the pull, so it is ignoring my duty numbers to try to reach the boost target. I guess it needs a little more duty cycle to reach the targets. I'll try that. Are the oscillations because it's trying to reach the targets without enough duty cycle perhaps?
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Old 04-18-2016, 10:55 PM   #30
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Ok, I think I got it by copying the 33 duty that it never went below in that last log I posted. It isn't oscillating wildly anymore, just a little bump past right at the beginning then it settles at 190 kpa. Please look at the current log and tune and tell me what I could do better. Boost by gear is working now.
Attached Files
File Type: msl 2016-04-18_18.31.28.msl (289.5 KB, 32 views)
File Type: msq CurrentTune.msq (242.9 KB, 33 views)
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