Results 1 to 11 of 11

Thread: Please help explain, Flow Rate / Injector Flow Rate Modifier vs. IAT

  1. #1

    Please help explain, Flow Rate / Injector Flow Rate Modifier vs. IAT

    This is on a 2011 Camaro, can someone explain the meaning of the values and there affect on fueling by increasing or decreasing?

    Will the value less than 1 (0.98, 0.97 etc.) decrease fueling or have the opposite affect.
    2011 Camaro, 430cu Lsx, Mast Heads, Ported TVS 2300, ID 1300's, E85-Flex, Squash Fuel System, 250 Direct Port Nitrous, LPE Overdrive rear 10/14 Rib, Overdrive, 2.8" Upper, NW 102, 2" ARH, PATC built A6, Circle D Conv. etc. BMR 15" Wheel Conversion w/29/10.5W's/15 Hoosiers

    2007 H2 SUT, 427 LSX, T76 BB@16lbs 225 Trickflows, Vic JR Intake, Lt's, Dual return fuel sys, Comp 236-232-115, 4L80e, 3000 Vigilante, etc.

  2. #2
    Anyone care to share inf?
    2011 Camaro, 430cu Lsx, Mast Heads, Ported TVS 2300, ID 1300's, E85-Flex, Squash Fuel System, 250 Direct Port Nitrous, LPE Overdrive rear 10/14 Rib, Overdrive, 2.8" Upper, NW 102, 2" ARH, PATC built A6, Circle D Conv. etc. BMR 15" Wheel Conversion w/29/10.5W's/15 Hoosiers

    2007 H2 SUT, 427 LSX, T76 BB@16lbs 225 Trickflows, Vic JR Intake, Lt's, Dual return fuel sys, Comp 236-232-115, 4L80e, 3000 Vigilante, etc.

  3. #3
    Senior Tuner SultanHassanMasTuning's Avatar
    Join Date
    Nov 2009
    Location
    All Around
    Posts
    3,149
    that table is a multiplier, 1 meaning same value output in your injector flow rate vs pressure (which no one changes)

  4. #4
    Quote Originally Posted by SultanHassanMasTuning View Post
    that table is a multiplier, 1 meaning same value output in your injector flow rate vs pressure (which no one changes)
    On my stock settings cells in the upper IAT range have values less than 1 (0.98, 0.97 etc) Would the values less than 1 effectivly lean or enrichen AFR?
    2011 Camaro, 430cu Lsx, Mast Heads, Ported TVS 2300, ID 1300's, E85-Flex, Squash Fuel System, 250 Direct Port Nitrous, LPE Overdrive rear 10/14 Rib, Overdrive, 2.8" Upper, NW 102, 2" ARH, PATC built A6, Circle D Conv. etc. BMR 15" Wheel Conversion w/29/10.5W's/15 Hoosiers

    2007 H2 SUT, 427 LSX, T76 BB@16lbs 225 Trickflows, Vic JR Intake, Lt's, Dual return fuel sys, Comp 236-232-115, 4L80e, 3000 Vigilante, etc.

  5. #5
    values less than 1 will decrease the injector flow rate, making the pulse width longer. From memeory this table tries to compensate for lower flows due to the higher fuel rail temps.
    I count sheep in hex...

  6. #6
    Quote Originally Posted by Chris@HPTuners View Post
    values less than 1 will decrease the injector flow rate, making the pulse width longer. From memeory this table tries to compensate for lower flows due to the higher fuel rail temps.
    Thanks for your reply.
    Sorry for probably having you repeat your answer but I am trying to better understand the principal. Decreasing the value would lengthen the pulse width and decreases injector flow rate. I had the impression that when I decrease the value in the flow rate table that it would result in enrichen my AFR. Do I have this backwards?
    If the purpose is to compensate for higher fuel rail temps should I assume you mean increase fuel supply by decreasing this value?
    2011 Camaro, 430cu Lsx, Mast Heads, Ported TVS 2300, ID 1300's, E85-Flex, Squash Fuel System, 250 Direct Port Nitrous, LPE Overdrive rear 10/14 Rib, Overdrive, 2.8" Upper, NW 102, 2" ARH, PATC built A6, Circle D Conv. etc. BMR 15" Wheel Conversion w/29/10.5W's/15 Hoosiers

    2007 H2 SUT, 427 LSX, T76 BB@16lbs 225 Trickflows, Vic JR Intake, Lt's, Dual return fuel sys, Comp 236-232-115, 4L80e, 3000 Vigilante, etc.

  7. #7
    Quote Originally Posted by DRTWRK View Post
    Thanks for your reply.
    Sorry for probably having you repeat your answer but I am trying to better understand the principal. Decreasing the value would lengthen the pulse width and decreases injector flow rate. I had the impression that when I decrease the value in the flow rate table that it would result in enrichen my AFR. Do I have this backwards?
    If the purpose is to compensate for higher fuel rail temps should I assume you mean increase fuel supply by decreasing this value?
    The idea of the table is to inform the ECM that the injector flow rate changes with temperature so the baseline fueling remains constant. Hotter fuel is less dense than cold fuel so when it's colder the actual flow rate is higher and when it's hotter it's lower. If this table didn't exist the fuel trims would need to work harder.
    I count sheep in hex...

  8. #8
    Advanced Tuner
    Join Date
    Jan 2008
    Posts
    242
    [QUOTE]Originally Posted by DRTWRK: If the purpose is to compensate for higher fuel rail temps should I assume you mean increase fuel supply by decreasing this value?
    Yes as Bill stated above:Hotter fuel is less dense than cold fuel. You can see that in the ZR1 file.

  9. #9
    Tuner OldFartC6's Avatar
    Join Date
    Jan 2008
    Location
    North GA
    Posts
    188
    Quote Originally Posted by Chris@HPTuners View Post
    values less than 1 will decrease the injector flow rate, making the pulse width longer. From memeory this table tries to compensate for lower flows due to the higher fuel rail temps.

    Some confusion here, don't you mean values less than 1 will decrease flow rate by making the pulse width shorter not longer?

  10. #10
    [QUOTE=C5 2000;322009]
    Originally Posted by DRTWRK: If the purpose is to compensate for higher fuel rail temps should I assume you mean increase fuel supply by decreasing this value?
    Yes as Bill stated above:Hotter fuel is less dense than cold fuel. You can see that in the ZR1 file.
    I see the ZR1 table seems to decrease values starting at 104* vs 140* in my file. Im I correct to assume the ZR1 will increase fuel by percentage of flow rate starting at a lower temp? If so, could this effect AFR on a OLSD tune where I do not use LTFT's. Bill mentioned that with the correct values fuel trims would not have to work so hard trying to compensate.
    2011 Camaro, 430cu Lsx, Mast Heads, Ported TVS 2300, ID 1300's, E85-Flex, Squash Fuel System, 250 Direct Port Nitrous, LPE Overdrive rear 10/14 Rib, Overdrive, 2.8" Upper, NW 102, 2" ARH, PATC built A6, Circle D Conv. etc. BMR 15" Wheel Conversion w/29/10.5W's/15 Hoosiers

    2007 H2 SUT, 427 LSX, T76 BB@16lbs 225 Trickflows, Vic JR Intake, Lt's, Dual return fuel sys, Comp 236-232-115, 4L80e, 3000 Vigilante, etc.

  11. #11
    Tuner
    Join Date
    Feb 2007
    Location
    Calgary
    Posts
    155
    Numbers less than 1 are richer because longer pulse widths are commanded to make up for the lower flow rate the ecm computes the injectors at.