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Thread: VE correction factor

  1. #1
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    VE correction factor

    Is VE correction factor the same as the VE predictive airflow that gets used in a blend SD and MAF tune? I'm running a two bar custom OS on a 2002 Tahoe flex fuel file. I've noticed that when I run SD only fueling is great, MAF only fueling is great, when I run a blended tune once I go over the my 2nd RPM zone boundary, dynamic airflow is under predicted (goes lean) and I think this is the VE predictive airflow going crazy because the VE predictive airflow coefficients (which we don't have access too) are not set-up for forced induction (turbo). Anyway, the VE correction factor min and max, are they limits on the VE predictive airflow calculation? Since I can't tune VE predictive airflow, I want to eliminated it, since my VE and MAF tables are dialed in. I'm thinking to either use the VE correction factor limits (if that works and has no other side effects) or raise the second RPM boundary above my High RPM disable limit to disable the VE predictive airflow calculation, which is messing up my fueling. VE predictive airflow doesn't seem to play a role until the second RPM boundary is crossed is that correct? Thanks.
    Phil K.
    02 Camaro SS 5.7L LS1
    01 Silverado 1500HD 6.0L LQ4 4L80E 78/75 turbo with Flex Fuel

  2. #2
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    I am having exact same issue with a truck i am tuning. 2003 5.3 running a maggy blower and 2bar. I am surprised no one else chimed in on this. I have perfect fueling in maf only and sd only but dynamic goes lean between 2800 to 4000rpm. The ve airflow dips while maf stays steady and correct. So the ecu is calculating incorrect ve values in that rpm range. Going to try lowering dyn high rpm from 4000 to 2500 and see what happens.
    2022 Camaro ZL1 6.2 Auto Black Stock

  3. #3
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    VE correction is used to calculate dynamic airflow based on the MAF/VE differences during transitions from steady state to not steady state. It is likely not your area to fix this.

    Log, at the same polling rate, dynamic airflow, MAF airflow, and VE airflow. Put them in a chart with the same upper and lower bounds and if they do not overlap each other (not perfectly but close) in steady state conditions you need to correct one of the MAF or VE tables.

  4. #4
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    curious if anyone has learned more about the ve corrections? due to them being temperature based(and baro) I would expect they could really mess with you when tuning SD only at lower temps from operating temp. Has anyone ran into this before? Also seems like they could be messing with you while trying to dial in VE as they could be floating around making the correction factors skewed from the absolute VE numbers you're trying to apply them to.

    I'm fixing to just set min and max to 0.999 and 1.001 and set table to all 1s and go from there. I'm getting a pig rich warm up idle on a SD P59 that once warm is perfect. Really racking my brain and this is all I can think it could be.

  5. #5
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    "I'm fixing to just set min and max to 0.999 and 1.001 and set table to all 1s and go from there." Same. Would love to just get a .bin file of HPTuners "custom" SD base tune to compare. Trying to get this all sorted without setting any DTCs.

  6. #6
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    The SD OSes do not handle the MAF any differently, it still works unless failed with the P0102/P0103 set as Current.
    Quote Originally Posted by SiriusC1024 View Post
    I think they're junkyard rebuilds.

  7. #7
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    Then I find it very curious the increase in stability I got by maxing out steady state MAP delta values without having a MAF plugged in or failed in any way.

  8. #8
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    Compared to what, exactly? With a MAF and the regular blended mode? If that's what you're talking about, then of course it ran better. Most people don't know that they run better in pure SD without the MAF, they assume that since the factory used MAF, and they want it to drive nice, then they need to use MAF as well.
    Quote Originally Posted by SiriusC1024 View Post
    I think they're junkyard rebuilds.

  9. #9
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    Instead of copy pasting my reply, see here https://forum.hptuners.com/showthrea...g-table-always

  10. #10
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    Dumb. Sorry.
    Quote Originally Posted by SiriusC1024 View Post
    I think they're junkyard rebuilds.

  11. #11
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    Yeah, guess I should have a swap solution that can't pass e-check, or pay $1,000+ for some Holley, Haltech, Fueltech, MaxxECU, bullshit, or some $400 Microsquirt thing that barely does V8 control and can't even control a transmission. Yeah, I'm fucking retarded over here, with my testing that refutes what an 'expert' claims.
    Last edited by MarcWolfe; 12-15-2024 at 09:52 AM.

  12. #12
    Tuning Addict edcmat-l1's Avatar
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    ^^^ Dude go away with your spam BS replies.

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  13. #13
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    Hmm, a paid tuner doesn't like elaborate detail being openly shared for free. Shocker.

  14. #14
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    So the idea here is, I wanna delete every sensor and control routine that isn't needed for the engine to run, so that I can pass a smog check.

    ...

    ...

    I wanna dig a big hole in my yard and fill it with various random bits of scrap metal and assorted chemicals, and hopefully it will spontaneously reconfigure itself into a spaceship.
    Quote Originally Posted by SiriusC1024 View Post
    I think they're junkyard rebuilds.

  15. #15
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    You want to go on about how I disabled PE too? The newer the car, the less compliant any enrichment is. But I'm just a retard...

  16. #16
    Tuning Addict edcmat-l1's Avatar
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    Quote Originally Posted by MarcWolfe View Post
    You want to go on about how I disabled PE too? The newer the car, the less compliant any enrichment is. But I'm just a retard...
    Pretty well sums it up.

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  17. #17
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    I'm still looking for some substance in anything you've replied to me.

  18. #18
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    Quote Originally Posted by MarcWolfe View Post
    I'm still looking for some substance in anything you've replied to me.
    This is someone else's 4 year old thread you bumped. I would not expect much of anything from it.

  19. #19
    Tuning Addict edcmat-l1's Avatar
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    Quote Originally Posted by MarcWolfe View Post
    I'm still looking for some substance in anything you've replied to me.
    We're still waiting for anything of substance from you.

    EFI specialist
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  20. #20
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    I didn't know pieces of shit could be so loud.
    You just troll the forum for my comments now?