Results 1 to 4 of 4

Thread: Graph different than chart gauge and channels?

  1. #1
    Potential Tuner
    Join Date
    Feb 2024
    Location
    CA
    Posts
    9

    Graph different than chart gauge and channels?

    In VCM editor dose anyone know why the graph displays wildly different values in comparison to the chart gauges or channels? I am logging a 2021 mustang gt pp.

  2. #2
    Moderator
    Join Date
    Mar 2014
    Location
    Raleigh, NC
    Posts
    6,347
    Quote Originally Posted by 2021mustangGTPP View Post
    In VCM editor dose anyone know why the graph displays wildly different values in comparison to the chart gauges or channels? I am logging a 2021 mustang gt pp.
    Would need to see your exact example but usually the channels data is showing you the actual last value received and graphs/gauges are interpolation more between data points. Also could be using a different channel with a very similar name or could have more/less resolution than the one you're comparing to.
    Post a log and tune if you want help

    VCM Suite V3+ GETTING STARTED THREADS / HOW TO's

    Tuner by night
    CPX Tuning
    2005 Corvette, M6
    ECS 1500 Supercharger
    AlkyControl Meth, Monster LT1-S Twin, NT05R's
    ID1000's, 220/240, .598/.598, 118 from Cam Motion

    2007 Escalade, A6
    Stock

  3. #3
    Advanced Tuner
    Join Date
    Jan 2022
    Location
    Southern California
    Posts
    365
    The data is delayed, and then, apparently, there is processing time in HP program. So for me, misc data can easily be a half sec off compared to other data.

    When I first got HP I was getting a total engine shutdown at the 1-2 shift at full throttle. I think, oh crap, I killed it! Then it recovers a second or so later. Rpms were well below the limiter, fuel psi good, no codes, no clues... So wth is it??? Turns out it was hitting the limiter, but HP couldn't see it, it's too slow. The dash gauge was also too slow because it also gets the data digitally. It was better than HP, but still delayed and still below redline. I figured it out when I raised the limiter and the problem went away, because what else could cause that other than the limiter.
    I then discovered there were two rpm channels, so I put both on the screen, plus the digital read on the far left in Channels. Well, you see how far off everything was. The colored arrows connect the PID in Channels to its gauge, so even that is fubar. In the pix the top channel (white arrow) read higher, but moments later the other channel was a good 300 higher. Basically the quicker the rpm change the further off they get from each other, and no clue which is closer to the truth. In this example I can only assume rpms were somewhere between 5000-6200?

    Spark retard from ping is another good example; I made a ping retard alarm out of a gauge in HP to let me know when it happens, but when I see it I have to go fwd quite a bit from that moment before the data shows up in Channels to see which cyl and by how much. Then I wonder how do I compare that to spark, rpm and load if I have no clue where any of them actually are in that moment? So all I can do is make a spark timing adjustment and see what happens.

    RPM problem.jpg
    '16 E550 Coupe RWD - C207.373 / M278.922 / MED17.7.3 / 722.909

  4. #4
    Senior Tuner
    Join Date
    Nov 2017
    Posts
    1,464
    Did you play with polling frequency?