Results 1 to 3 of 3

Thread: LF4 engine converted to multiport FI from direct injection question

  1. #1
    Potential Tuner
    Join Date
    Mar 2015
    Posts
    5

    LF4 engine converted to multiport FI from direct injection question

    Hello, I am interested in converting an LF4 from direct injection to port fuel injection.

    My question is- are the DI injectors offset a certain degree crank rotation so they spray once the intake valve is closed?

    The thing I want to make sure I avoid is the port fuel injectors spraying fuel after the valve is closed, which would result in them spraying fuel on the back side of the closed intake valve.

  2. #2
    Advanced Tuner
    Join Date
    Jan 2004
    Location
    Columbus, Ohio
    Posts
    213
    Yes, check table 33913 - Injector SOI Base. Here you can program the start of the injection angle (SOI) in crankshaft degrees BTDC.
    2022 Cadillac CT5-V Blackwing (733 whp)
    2022 Cadillac CT4-V Blackwing (716 whp), 10.750 @ 134.77 mph
    2016 Cadillac ATS-Vs (eleven ATS-Vs in the 9s)
    2008 Pontiac G8 (first G8 in the 10s), 10.727 @ 129.87 mph
    2000 Bonneville SSEi (first 3800 Bonneville in the 10s), 10.711 @ 125.71 mph
    1999 Grand Prix GT (first 3800 FWD in the 8s), 8.902 @ 154.90 mph
    1998 Firebird (first 3800 RWD in the 8s), 843 whp, 8.991 @ 152.12 mph
    1998 Grand Prix GTP (first 3800 FWD in the 10s), 9.499 @ 145.13 mph

  3. #3
    Potential Tuner
    Join Date
    Mar 2015
    Posts
    5
    Awesome, thanks Mr. INTENSE!
    Last edited by KINGVEE; 10-15-2019 at 10:52 AM.