isac boost control issue (high boost)

Discussion in 'Alcohol, Nitrous and Propane Tech' started by VIN7, Jan 29, 2012.

  1. VIN7 Member

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    TurboBob,

    Had some runs today, target boost at 24.6, 26.6 and 28.2. The .isa is the same for all, I didn't make any changes. isac did a good job for the 24 and 26 psi but 28 looked like it couldn't control too well.

    Do you have any suggestions for the high boost scenario? Also, I have max dc at 85% yet it seemed to go over 85%.

    Thanks,
    Mike

    Attached Files:

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  3. TurboBob Tater Salad

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    The boost control mode is not switching from spool to ON on the last run. This is preventing the unit from resolving the boost creep. I can look into the software and see whats up there. If you look at the end of the run, the mode changes and the unit gets it under control better.

    The min and max dutycycles are only used to predict what the dutycycle will be on the spoolup, they don't limit how far the DC can go. It looks like your system is tuned decently otherwise.

    Your wideband gave up on that run also.

    B
  4. VIN7 Member

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    Thanks Bob.

    The LC-1 has freaked out a couple of times during a run, luckily the fuel correction is limited to -10%. Time to look into the AEM or ??? that are more stable.

    Let me know what you come up with on the mode deal.

    Mike
  5. TurboBob Tater Salad

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    exactly which version are you running in the unit (not the PC program version)?

    My LC1 has been good over the years, but others have had issues.... at the very least set the failure output mode to swing full lean on an error.

    AEM and PLX have been good for some friends.

    Bob
  6. VIN7 Member

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    ICC version 1.9.0

    The LC-1 is set to go to 14.5 in case of an error, but I don't know if it was an error or a corruption of data output because it started reading correctly after I let off the throttle.

    Also, have you noticed a difference in afr reading depending on sensor location? I have it in the last bend before the test pipe, I see a lot of people have it about 8" from the turbo outlet. Just wondering if my target of 10.8 is actually richer than the same target 8" from the turbo outlet.
  7. JayC T6P.Com/TB.com Administrator/Webmaster

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    Where you have them is where I put them. If you put a LC-1 that close to the turbo, the sensor will fail sooner than later.

    I had good luck with the PLX unit. The AEM unit, not so much but the PLX was what we were using at BWR before the shutdown.
  8. TurboBob Tater Salad

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    What version is in the ISAC itself?
  9. TurboBob Tater Salad

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    here, give this one a try. I changed the spool to run transition to fix the problem with run4, and set the run gain to be able to correct further as it was running out of range (you have a LOT of boost creep).

    My car is off the road, so I can't test it live.

    Bob

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  10. VIN7 Member

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    Bob,

    Reflashed and now the boost gauge always reads 20.xx and there is hardly any trim knob adjustment for target boost. This is KOEO, with some adjustments to activate the solenoid w/o the engine running.

    Mike

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  11. VIN7 Member

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    Oops, helps if I setup the right map sensor setting.
  12. VIN7 Member

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    User error, I reflashed to 1.9.3 and I loaded my last known isa. Are there any settings you want me to change (gain)?

    Here's the log of me sitting KOEO playing with the trim knob, min and max are perfect for what I want to do.

    Attached Files:

  13. TurboBob Tater Salad

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    no, the software update is a drop-in. I didn't change anything with the control parameters (gains).

    I'm on the wrong computer, I will look at your files later on. But the settings you had before looked right on.

    B
  14. VIN7 Member

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    Bob,

    Here is just a quick stab with the new software, boost went way above target but the isac only dropped duty cycle to 85%???

    Mike

    Attached Files:

  15. VIN7 Member

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    No wideband signal, recently updated to PLX but haven't wired it to isac.
  16. TurboBob Tater Salad

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    thats really wierd, you just loaded the file I sent and then reloaded your tune, right? The dutycycle isn't calculating right.....

    I'll go back turn it this weekend and test run it using your settings.

    In the mean time, go back to the previous version, at moderate boost it ran pretty well.

    Bob


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