Results 1 to 10 of 10

Thread: VE after logging

  1. #1
    Lifetime Member Beer99C5's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default VE after logging

    OK with the help of TA Quickness and dfe1 (provided me his 6101 Table), I have completed using the VE Tutorial.

    Before I upload the new tune, just want to make sure it looks right.

    Here are my values for BenX



    Here is my count for BenX




    Here is the table applied to the tune






    I guess my question is what about the cells i did not hit on? Do I need to smooth or blend? Looks like I can interpolate @ 800 RPM for 70-85 Kpa

    This OK to load these new tables to the stock tune to then check the LTFT's?
    1999 C5 A-4 Convertible
    1 of 245 Nassua Blue 99 Vert's, Blackwing, LS6 Intake, 42 # Injectors, Two Stage Nitrous System- Dry and a Wet Plate, EFI Live Scan/Tune V2, 1999 PCM with 2002 COS 5 OS Custom Nitrous Panel.


    Maine USA



  2. #2
    Lifetime Member TAQuickness's Avatar
    Join Date
    Jan 2005
    Posts
    2,940

    Default

    you will want to get thru the entire VE table at somepoint


  3. #3
    Senior Member
    Join Date
    Dec 2005
    Posts
    172

    Default

    Wow. Newb question. In the higher rpm's and kPa, The higher the number, the more fuel it will give?

  4. #4
    Senior Member
    Join Date
    Oct 2005
    Posts
    196

    Default

    Your BEN average values are not good enough yet. They need to be around the 1.00 value + or - .01. This will probably take you a few more tries as each time you collect the data and apply it to your VE table the BEN's get closer to 1. After you've gotten your BEN's around 1 you will then do a calibration comparison between your original VE table and your new one based on your AutoVE tuning and apply to your original VE table in your original tune. It's after this point that you will then disable the MAF in your original tune and re-enable your 02's so you can log LTFT's to see how they are (should be around zero or slightly negative). If not there yet, repeat the whole procedure. Hope this is helpful and good luck.


  5. #5
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    Quote Originally Posted by 12sec.5.3
    Wow. Newb question. In the higher rpm's and kPa, The higher the number, the more fuel it will give?
    That's not how it works, although you may/will get more fuel...

    The VE table gives the cylinder airmass (taking temp and pressure into account, it really has units g.K/kPa);

    then the airmass is divided by the commanded AFR (from OLFA and/or PE tables) to give the fuelmass;

    then the fuelmass is divided by the IFR to give the injector pulse width.

    So basically, after you get the VE table corrected, you control the amount of fueling from the OLFA/PE tables;
    once the VE table is corrected, you will see that the wideband AFRs will exactly follow the OLFA/PE tables.

  6. #6
    Lifetime Member
    Join Date
    Jul 2005
    Posts
    702

    Default

    Quote Originally Posted by joecar
    That's not how it works, although you may/will get more fuel...

    The VE table gives the cylinder airmass (taking temp and pressure into account, it really has units g.K/kPa);

    then the airmass is divided by the commanded AFR (from OLFA and/or PE tables) to give the fuelmass;

    then the fuelmass is divided by the IFR to give the injector pulse width.

    So basically, after you get the VE table corrected, you control the amount of fueling from the OLFA/PE tables;
    once the VE table is corrected, you will see that the wideband AFRs will exactly follow the OLFA/PE tables.
    ha! it's nice to see someone putting my work to good use already

  7. #7
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    I summarised your equations/explanations...

  8. #8
    Lifetime Member
    Join Date
    Jul 2005
    Posts
    702

    Default

    so does that mean that my paper gets full approval?

  9. #9
    Lifetime Member Beer99C5's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default

    Quote Originally Posted by joecar
    That's not how it works, although you may/will get more fuel...

    The VE table gives the cylinder airmass (taking temp and pressure into account, it really has units g.K/kPa);

    then the airmass is divided by the commanded AFR (from OLFA and/or PE tables) to give the fuelmass;

    then the fuelmass is divided by the IFR to give the injector pulse width.

    So basically, after you get the VE table corrected, you control the amount of fueling from the OLFA/PE tables;
    once the VE table is corrected, you will see that the wideband AFRs will exactly follow the OLFA/PE tables.
    Hey I understand what joecar is saying now! Thanks redhardsupra!

    Quote Originally Posted by VetPet
    Your BEN average values are not good enough yet. They need to be around the 1.00 value + or - .01. This will probably take you a few more tries as each time you collect the data and apply it to your VE table the BEN's get closer to 1. After you've gotten your BEN's around 1 you will then do a calibration comparison between your original VE table and your new one based on your AutoVE tuning and apply to your original VE table in your original tune. It's after this point that you will then disable the MAF in your original tune and re-enable your 02's so you can log LTFT's to see how they are (should be around zero or slightly negative). If not there yet, repeat the whole procedure. Hope this is helpful and good luck.

    OK I had not actually applied the new values yet, I was just checking to make sure I was on track.

    Thanks for the help
    1999 C5 A-4 Convertible
    1 of 245 Nassua Blue 99 Vert's, Blackwing, LS6 Intake, 42 # Injectors, Two Stage Nitrous System- Dry and a Wet Plate, EFI Live Scan/Tune V2, 1999 PCM with 2002 COS 5 OS Custom Nitrous Panel.


    Maine USA



  10. #10
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    28,403

    Default

    Quote Originally Posted by redhardsupra
    so does that mean that my paper gets full approval?
    Almost... I want to reread it...

    On page 8 (version 1.04):

    you leave the CylinderCount right out of the TheoreticalAirflow equation and out of the VE equation that follows
    (and of course resulting VE at the end also, as you should)...

    but, the previous paragraph or two shows the Airflow equation with CylinderCount in it;

    so I think it would be an instructive intermediate step to put CylinderCount in the TheoreticalAirflow equation,
    and show CylinderCount being in the numerator and denominator of the ensuing VE equation (i.e. showing that it cancels out)...

    and then this leads very nicely to the universal equation VE = GMVE * R/Volume (which is what you have);
    that's a very nice wrap up, showing that equation is very fundamental.

    BTW: good job on the units analysis, keeps a good sanity check.

    BTW: I like the G.I.Joe graphic at the very end, nice touch.

Similar Threads

  1. Logging LMM's
    By schuter in forum Diesel
    Replies: 5
    Last Post: March 20th, 2008, 02:26 AM
  2. Logging L76
    By JezzaB in forum Gen IV V8 Specific
    Replies: 0
    Last Post: June 11th, 2007, 11:10 PM
  3. Logging RPM
    By oztracktuning in forum Black Box Logging
    Replies: 3
    Last Post: January 20th, 2006, 06:55 PM
  4. I have a few Q's about logging.
    By SmaknSS in forum General
    Replies: 3
    Last Post: December 1st, 2005, 06:33 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •