Page 1 of 2 12 LastLast
Results 1 to 20 of 29

Thread: Acceleration Rate Math Parameter

  1. #1
    Advanced Tuner
    Join Date
    Aug 2010
    Posts
    215

    Acceleration Rate Math Parameter

    Here's an acceleration math parameter. Try it and let me know what you guys think. Please provide feedback.

    The higher the number, the more torque/hp you're making. Doesn't read horsepower, it reads acceleration rate.

    <?xml version="1.0" encoding="UTF-8"?>
    <MathParameter Notes="([13.114.avg(-1000)])-([13.114.avg(+1000)])" Decimals="3" Unit="155" Expression="([13.114.avg(-1000)]) - ([13.114.avg(+1000)])" Abbreviation="" Name="Accel Rate" />

  2. #2
    Senior Tuner mowton's Avatar
    Join Date
    Mar 2007
    Location
    Florida
    Posts
    3,773
    Quote Originally Posted by SVT_Z06 View Post
    Here's an acceleration math parameter. Try it and let me know what you guys think. Please provide feedback.

    The higher the number, the more torque/hp you're making. Doesn't read horsepower, it reads acceleration rate.

    <?xml version="1.0" encoding="UTF-8"?>
    <MathParameter Notes="([13.114.avg(-1000)])-([13.114.avg(+1000)])" Decimals="3" Unit="155" Expression="([13.114.avg(-1000)]) - ([13.114.avg(+1000)])" Abbreviation="" Name="Accel Rate" />
    Playing with it now, set up an old log with rpm/spark advance graph off a dyno to check it out. Will figure out a graph with g/cyl to track cylinder load as well. Will report back when I have it figured out.

    Suggest you use the Generic Vehicle speed parameter so it works with all platform/OS's... ([50020.110.avg(-1000)])-([50020.110.avg(1000)])

    Thanks for sharing...

    Ed M
    2004 Vette Coupe, LS2, MN6, Vararam, ARH/CATs, Ti's, 4:10, Trickflow 215, 30# SVO, Vette Doctors Cam, Fast 90/90, DD McLeod, DTE Brace, Hurst shifter, Bilsteins etc. 480/430

    ERM Performance Tuning -- Interactive Learning ..from tuning software training to custom tunes
    HP Tuners Dealer- VCM Suite (free 2hr training session with purchase), credits and new Version 2.0 turtorial available
    http://www.ermperformancetuning.com
    http://www.facebook.com/ERMPerformanceTuning

    [email protected]

  3. #3
    Advanced Tuner
    Join Date
    Aug 2010
    Posts
    215
    You're welcome! Please share findings or any additions that would be helpful.

  4. #4
    Advanced Tuner
    Join Date
    Aug 2010
    Posts
    215

    Working good

    This seems to be working good.

    Added a screenshot of my 1/8 mile run showing much wheel spin (see arrows).
    Attached Images Attached Images

  5. #5
    For some reason I can't get mine to display anything besides zero. I changed the expression in the XML file to use 50020.110 as mowton suggested and I am logging SAE vehicle speed? Isnt there also a way to log and use undriven wheel speed so we can ignore any wheel spin? Or does SAE already account for this? I think it does?

  6. #6
    Advanced Tuner
    Join Date
    Aug 2010
    Posts
    215
    Quote Originally Posted by cmitchell17a View Post
    For some reason I can't get mine to display anything besides zero. I changed the expression in the XML file to use 50020.110 as mowton suggested and I am logging SAE vehicle speed? Isnt there also a way to log and use undriven wheel speed so we can ignore any wheel spin? Or does SAE already account for this? I think it does?
    Should work. Try entering the math in user math 10 or higher. Try using my expression too.

    Vehicle speed SAE is what I am using.

    Not sure about undriven wheel speed. I personally think its helpful when logging track runs.

    For power/comparisons, I log third gear runs at wot with no spinning...just smooth wot.

  7. #7
    I think it might be something in the way I'm entering the expression. I tried both copying the whole:

    <?xml version="1.0" encoding="UTF-8"?>
    <MathParameter Notes="([13.114.avg(-1000)])-([13.114.avg(+1000)])" Decimals="3" Unit="155" Expression="([13.114.avg(-1000)]) - ([13.114.avg(+1000)])" Abbreviation="" Name="Accel Rate" />

    into the xml file and I tried a new parameter in user math 10 with just putting:

    ([13.114.avg(-1000)]) - ([13.114.avg(+1000)])

    in the expression box but neither worked
    Last edited by cmitchell17a; 01-07-2018 at 05:50 PM.

  8. #8
    Senior Tuner
    Join Date
    Jan 2014
    Location
    Australia
    Posts
    1,970
    i dont know how much power u are running but any decent hp will get alot of wheel spin even if u cant feel it so it would be best to use undriven wheel speed, i always log both driven/undriven and am amazed at the difference sometimes

  9. #9
    Advanced Tuner
    Join Date
    Aug 2010
    Posts
    215
    Quote Originally Posted by cmitchell17a View Post
    I think it might be something in the way I'm entering the expression. I tried both copying the whole:

    <?xml version="1.0" encoding="UTF-8"?>
    <MathParameter Notes="([13.114.avg(-1000)])-([13.114.avg(+1000)])" Decimals="3" Unit="155" Expression="([13.114.avg(-1000)]) - ([13.114.avg(+1000)])" Abbreviation="" Name="Accel Rate" />

    into the xml file and I tried a new parameter in user math 10 with just putting:

    ([13.114.avg(-1000)]) - ([13.114.avg(+1000)])

    in the expression box but neither worked
    Email me your main layout xml file. [email protected]. Also, what kind of car/pcm are you using this on?

  10. #10
    Advanced Tuner
    Join Date
    Aug 2010
    Posts
    215
    Quote Originally Posted by 07GTS View Post
    i dont know how much power u are running but any decent hp will get alot of wheel spin even if u cant feel it so it would be best to use undriven wheel speed, i always log both driven/undriven and am amazed at the difference sometimes
    How do you log them?

  11. #11
    I found my problem to be not using at least "User Math 10" or higher when creating a new math parameter you have to enter it into 10 or higher for some reason.

  12. #12
    Senior Tuner
    Join Date
    Jan 2014
    Location
    Australia
    Posts
    1,970
    Quote Originally Posted by SVT_Z06 View Post
    How do you log them?
    they should be listed in the scanner they were added a while ago ill see if i can list then when im back on laptop

  13. #13
    Senior Tuner
    Join Date
    Jan 2014
    Location
    Australia
    Posts
    1,970

  14. #14
    I see acceleration even when SAE vehicle speed is 0:
    Capture.PNG

    This was during launch control though It looks like I didn't have the brake applied good enough and it jumped a little.

  15. #15
    So I made a histogram against RPM and filtered it for WOT tps only, this is showing MAX values not averaged values, since there are some outliers:
    Capture.PNG

    I am trying to answer the question of weather there is more acceleration at peak HP or peak torque, this seems to reveal peak HP. I'm sure you could derive the math some how to prove it.

  16. #16

    Comparing tune changes without dyno

    I've been experimenting with Virtual Dyno for a couple hours, and just found this thread. Haven't tried the math parameter yet. Looking for the best/easiest a way to quantify the power difference between tunes without a dyno and figured others must have been down this road before (pun intended). Any advice appreciated!

  17. #17
    Tuner
    Join Date
    Feb 2017
    Location
    Billings,MT
    Posts
    97
    What channels need to be added for this to work? I wouldn't mind playing with this when my car gets out of storage. And can it be done with the histogram to see the HP/TQ and certain RPM? And if I log the run can it be changed to work with that Virtual Dyno for comparison? Then I can compare it to the dyno I've already done on a Mustang AND the one I'll do on a Dynojet! This should be a fun play time as well!!

  18. #18
    Quote Originally Posted by XxScottxXN View Post
    What channels need to be added for this to work? I wouldn't mind playing with this when my car gets out of storage. And can it be done with the histogram to see the HP/TQ and certain RPM? And if I log the run can it be changed to work with that Virtual Dyno for comparison? Then I can compare it to the dyno I've already done on a Mustang AND the one I'll do on a Dynojet! This should be a fun play time as well!!
    I still haven't tried the math parameter, but here's what I've learned about using Virtual Dyno for tuning: Virtual Dyno needs RPM and TPS, but KR, eq ratio, spark advance, MAP, IAT, are good for diagnosis. Faster sample rates should be better, but experiment and look at the graph without smoothing to see what works best. You'll manually enter data for your car (weight, drag coefficient, frontal area, gear ratio, tire diameter, etc.) unless its popular enough to be in the program to choose from. Even if this data is off, comparisons are still valid with the same vehicle. Export the run (2nd gear seems best on mine) to .csv format, zoom in on the area of interest and export only that data. Edit the .csv file manually to delete the non full throttle portion. In Virtual Dyno, uncheck the "auto trim TPS" feature (if the car has an e-throttle that doesn't open fully at lower RPM's).

    It's been repeatable, differences have been traceable back to KR and/or a difference in the tune.
    Last edited by Mr.T; 03-14-2018 at 01:53 AM. Reason: Added experimenting with sample rates...

  19. #19
    Tuner in Training BadAquaBluSS's Avatar
    Join Date
    Feb 2013
    Posts
    28

    Acceleration math unit

    I know this is an old thread, however I'm interested in the acceleration math, is it possible for you to tell me how it's done, I've used the formulas here but my acceleration rate matches my mile per hour, not a percentage like yours shows, I watch the video on it and it says to use mile per hour per second however I don't see that as a unit, in the formulas above it shows unit 155 but no way to input it , or is it? Would it be possible for you to screenshot the math your using , and maybe a screenshot of the chart display editor I'm using version 4.0.12, Thank you in advance

  20. #20
    Quote Originally Posted by BadAquaBluSS View Post
    I know this is an old thread, however I'm interested in the acceleration math, is it possible for you to tell me how it's done, I've used the formulas here but my acceleration rate matches my mile per hour, not a percentage like yours shows, I watch the video on it and it says to use mile per hour per second however I don't see that as a unit, in the formulas above it shows unit 155 but no way to input it , or is it? Would it be possible for you to screenshot the math your using , and maybe a screenshot of the chart display editor I'm using version 4.0.12, Thank you in advance
    I just put "([50020.110.avg(-1000)])-([50020.110.avg(1000)])" in the expression field, and for the units I just put kilometers per second squared. I think we could change it to use undriven wheel speed but im not sure the ID to use. Make sure to use User Math 10 input or above.

    I haven't tried virtual dyno in a while, but last time I tried to use it I could never quantify any repeatable power differences between tunes Ive made, I could however quantify a repeatable power increase from gas to E85 and from tour and track mode on the NPP exhaust. Both indicated the correct power each should provide, ~5hp for the NPP exhaust and ~20hp for E85. The problem I found with it though is data below 3500rpm would not be accurate and would have random peaks in it. Im not sure if this was maybe because of the TC not being fully locked. I will try to experiment with it more. For as simple as an operation we are trying to do, just compare different logs to see an increase in power using acceleration, this should be simpler than it is. Using virtual dyno is still kind of a pain since you have to export the data as a CSV file and trim it then put it into virtual dyno. All this could be automated and instant.