Page 2 of 3 FirstFirst 123 LastLast
Results 21 to 40 of 41

Thread: Start of Injection calculator

  1. #21
    Senior Tuner mowton's Avatar
    Join Date
    Mar 2007
    Location
    Florida
    Posts
    3,773
    Quote Originally Posted by DSteck View Post
    The fuel rail pressure comes from the scanner.

    Yes, the offsets and multipliers would change. I hid the cells where I convert those to an equation (offset is actually three equations because it doesn't follow an overall trend).
    Thank you Dave, cant wait to give it a try on the next C7

    One other novice question, which scanner PID for fuel rail pressure?

    Ed M
    Last edited by mowton; 02-28-2015 at 01:50 PM.
    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]

  2. #22
    Senior Tuner DSteck's Avatar
    Join Date
    Mar 2008
    Location
    St. Louis, MO
    Posts
    4,856
    It's just actual rail pressure. I don't remember the exact name.

    DSX Tuning - Authorized HP Tuners Dealer
    http://www.dsxtuning.com
    http://www.facebook.com/dsx.tuning
    Just say no to bull s***.
    IF YOU WANT HELP, POST A FILE!

  3. #23
    Senior Tuner
    Join Date
    Dec 2004
    Location
    Laurel, MD
    Posts
    1,020
    why cant i click on any green fields?

  4. #24
    Tuner in Training
    Join Date
    Dec 2010
    Location
    Richmond, VA
    Posts
    40
    Very nice spreadsheet Dave!
    SHUETUNING
    Powertraincontrolsolutions

  5. #25
    Senior Tuner mowton's Avatar
    Join Date
    Mar 2007
    Location
    Florida
    Posts
    3,773
    Used it on a 2014 C7 SC (7# boost) setup and it worked great. Saw I was in the window with room to spare.

    Thanks again Dave

    Ed M

    PS -- Did find the PID :-)
    Last edited by mowton; 04-19-2015 at 12:30 PM.
    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]

  6. #26
    Senior Tuner Higgs Boson's Avatar
    Join Date
    Mar 2010
    Location
    Texas Hill Country
    Posts
    3,299
    I am still interested to see if anyone has tried spraying during the compression stroke or found out the latest we can fire the injector (for any given condition including idle).

    I know we don't HAVE to change anything except for at WOT and only if needed, but I am still curious.

    I know GM uses homogenous burn rather than lean burn but I would love to know if we can override that with SOI tables.

    Using this calculator shows I can lower the SOI table a LOT with NA applications and I am wondering why GM didn't use lower values/later injection timing.

  7. #27
    Senior Tuner DSteck's Avatar
    Join Date
    Mar 2008
    Location
    St. Louis, MO
    Posts
    4,856
    Probably emissions. That's usually what's behind everything. Lol.

    DSX Tuning - Authorized HP Tuners Dealer
    http://www.dsxtuning.com
    http://www.facebook.com/dsx.tuning
    Just say no to bull s***.
    IF YOU WANT HELP, POST A FILE!

  8. #28
    Senior Tuner
    Join Date
    Sep 2008
    Posts
    1,668
    Quote Originally Posted by Higgs Boson View Post
    I am still interested to see if anyone has tried spraying during the compression stroke or found out the latest we can fire the injector (for any given condition including idle).

    I know we don't HAVE to change anything except for at WOT and only if needed, but I am still curious.

    I know GM uses homogenous burn rather than lean burn but I would love to know if we can override that with SOI tables.

    Using this calculator shows I can lower the SOI table a LOT with NA applications and I am wondering why GM didn't use lower values/later injection timing.
    Have you guys found later timing improves power? I'm tuning a friends ZO6 (just bolt on's) and I'm currently well within the window to get the fuel in before the cutoff...I'm just not sure if moving the injection will be worth it.
    2010 Camaro SS M6. Stock Bottom End, Heads/Cam/Intake/Headers/Exhaust.
    2005 Silverado RCSB. Forged 370 LQ9/Borg-Forced Inductions T6 S484/Jake's Stage 4 4L80E with D3 Brake/4WD.
    2023 Durango Hellcat

  9. #29
    Senior Tuner Higgs Boson's Avatar
    Join Date
    Mar 2010
    Location
    Texas Hill Country
    Posts
    3,299
    I don't think it will hurt to pull it back to EVC over maybe 3500 RPMs.

  10. #30
    this spreadsheet should technically also work for the 5.3 L83 DI engines in the trucks correct?

  11. #31
    Senior Tuner Higgs Boson's Avatar
    Join Date
    Mar 2010
    Location
    Texas Hill Country
    Posts
    3,299
    yes

  12. #32
    Sorry to pull back this thread from dead
    I still didn't get the idea from this spread sheet
    should we add the injection duration to the SOI to get final result which should we use in SOI base table ?

  13. #33
    Excellent info Ben! Thanks a bunch.

  14. #34
    Senior Tuner
    Join Date
    Jun 2004
    Location
    Baltimore, Md
    Posts
    1,204
    Quote Originally Posted by Ben Charles View Post

    In the other thread about "injection Timing" I was going to post some graphs I made that show what I am about to mention. So without visual aid, hope this helps or makes sense.
    The C7 stock cam is 200/207 116.5 LSA (don't know if its advanced factory, so say intake centerline is straight up at 116.5, again VVT CAN/WILL COME INTO ACTION HERE)
    This means the stock cam
    IVO is -16.5 ATDC (normally cams are before BTDC, but factory cams are VERY SMALL)
    EVC is -13.0 BTDC
    So a 360 degree crank rotation shows the LT1 STOCK at WOT around 335, I say that number on a stock cam (centerline straight up) can be increased to around 343.5, but the exhaust Valve closes at 373 degrees, so technically between 343.5 and 373 injection could start

    NOW lets see what happens when you retard the camshaft say 6 degrees up top
    IVO is now -10.5 and EVC is -19 so essentially SOI can now be increased to 350 to 379 roughly. You can play with VVT throughout the entire RPM making changes.

    Stock C7 Z06 has SOI at WOT around 354
    Stock cam is 189/223 120 LSA (again centerline guessing straight up at 120LSA, again VVT changes this
    IVO is -25.5 ATDC
    EVC is -8.5 BTDC
    The ZO6 is injecting much earlier, there doing this for 2 reason I believe, 1 more fuel being injected and 2 to increase cylinder pressure to make more power for the given setup.
    Looking at injection they can inject anywhere up to 368.5 degrees with the cam straight up.

    IF anyone has any input, please share, this is what I cam up with doing some math and looking at the given values.
    Your saying can start at (360 plus IVO) up to (360 minus EVC)

    343.5-373 LT1
    335-368 LT4 retarded 8 degrees 326-360

    If you have aftermarket cam though 226/240 116 LSA
    363-360 on 110 centerline (negative window?), 353-368 if retarded 10 degrees from there

    That doesnt seem to make much sense. Plus you guys are using .050 numbers the valves dont actually open/close until 50 some degrees later/earlier
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  15. #35
    Senior Tuner Higgs Boson's Avatar
    Join Date
    Mar 2010
    Location
    Texas Hill Country
    Posts
    3,299
    Quote Originally Posted by GrannySShifting View Post
    Your saying can start at (360 plus IVO) up to (360 minus EVC)

    343.5-373 LT1
    335-368 LT4 retarded 8 degrees 326-360

    If you have aftermarket cam though 226/240 116 LSA
    363-360 on 110 centerline (negative window?), 353-368 if retarded 10 degrees from there

    That doesnt seem to make much sense. Plus you guys are using .050 numbers the valves dont actually open/close until 50 some degrees later/earlier
    you have room to spray after EVC at idle and normal loads and will have to spray earlier under high load if you have enough power. keep in mind that if the piston is on the downstroke (360 or less) then you have a better chance of keeping the fuel in the cylinder anyways.

    IMO, spray as late as possible that still keeps the engine running smoothly at lower RPMs and spray as late as possible at WOT that keeps your pulse width down (like below 5ms if possible), IMO, you really need meth or port injectors if you are going over 360 and still blowing through IPW.

  16. #36
    Senior Tuner
    Join Date
    Jun 2004
    Location
    Baltimore, Md
    Posts
    1,204
    Quote Originally Posted by Higgs Boson View Post
    you have room to spray after EVC at idle and normal loads and will have to spray earlier under high load if you have enough power. keep in mind that if the piston is on the downstroke (360 or less) then you have a better chance of keeping the fuel in the cylinder anyways.

    IMO, spray as late as possible that still keeps the engine running smoothly at lower RPMs and spray as late as possible at WOT that keeps your pulse width down (like below 5ms if possible), IMO, you really need meth or port injectors if you are going over 360 and still blowing through IPW.
    Using this log as an example, what would you do with SOI wot? Ms @ 5.2 peak dropping to 5.2. Trying to chase this KR Im pretty sure is false all around.
    Attached Files Attached Files
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  17. #37
    Advanced Tuner
    Join Date
    Jun 2007
    Location
    Close to my Z06
    Posts
    271
    How does the AFR/Lambda get affected by this? lets say you are dialed in to a .84 lambda then do mod the SOI, any changes?

  18. #38
    Tuning Addict
    Join Date
    Jan 2015
    Location
    Franklin, NC / Gainesville, Ga
    Posts
    6,736
    Depends if your burning cleaner or not... Yes this does apply to DI engines too - more so when you combine hpfp pressure changes with injection changes though...
    2010 Vette Stock Bottom LS3 - LS2 APS Twin Turbo Kit, Trick Flow Heads and Custom Cam - 12psi - 714rwhp and 820rwtq / 100hp Nitrous Shot starting at 3000 rpms - 948rwhp and 1044rwtq still on 93
    2011 Vette Cam Only Internal Mod in stock LS3 -- YSI @ 18psi - 811rwhp on 93 / 926rwhp on E60 & 1008rwhp with a 50 shot of nitrous all through a 6L80

    ~Greg Huggins~
    Remote Tuning Available at gh[email protected]
    Mobile Tuning Available for North Georgia and WNC

  19. #39
    Advanced Tuner
    Join Date
    Jun 2007
    Location
    Close to my Z06
    Posts
    271
    in the spreadsheet, it calls for inputting AFR, is that actual wideband read or commanded? also, since we need to power at wot open, over the 1.36, why would some populate pretty much all the area?

  20. #40
    Tuner in Training
    Join Date
    May 2017
    Posts
    30
    Sorry to pull back this thread again,

    When I use the C7 Z06 spread sheet with 6500 rpm, 20Mpa , 18 Spark Advance and 6ms IPW, it tells SOI would be 261.6*. In my calculation, if I start to spray 261.6*, I spary btw the mid of downstroke and just before the ignition (during compression stroke). Is it right and is it ok to spray during the compression?