Page 1 of 4 123 ... LastLast
Results 1 to 10 of 39

Thread: E39 lfx kr

  1. #1
    Lifetime Member Rhino79's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default E39 lfx kr

    Anyone noticing a rediculous amount of KR at wot with premium fuel. I have reduced the timing a bit and still seems to be showing crfazy knock. Ive drained the tank and refilled and still the same. Is this normal and are the kr settings overly sensative in this ECM?
    Head Calibrator
    Gwatney Performance Innovation
    Jacksonville, AR 501-982-2102

  2. #2
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    27,726

    Default

    Post log files.

  3. #3
    Forum tyhee Site Admin GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    12,734

    Default

    Not only seen it, you can hear them knocking sometimes , well, that is on the LFW I must admit, but isn't the LFX just a bigger version of that engine?
    Need official EFILive help, please go here.
    For tuning support please post your questions on this forum (or other auto forums).
    Sorry if I don't respond to your PM, don't take it personal.


  4. #4
    Lifetime Member Rhino79's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default

    10:1 compression (stock is 11.6:1), stock engine with forged pistons and twin 62s on 93 octane, zl1 pump and running 50/50 water meth.
    Attached Files Attached Files
    Head Calibrator
    Gwatney Performance Innovation
    Jacksonville, AR 501-982-2102

  5. #5
    Forum tyhee Site Admin GMPX's Avatar
    Join Date
    Apr 2003
    Posts
    12,734

    Default

    Ahhh, ok, that's a little different then. LFX is E85 capable right?
    Need official EFILive help, please go here.
    For tuning support please post your questions on this forum (or other auto forums).
    Sorry if I don't respond to your PM, don't take it personal.


  6. #6
    Lifetime Member Rhino79's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default

    I have enough fuel system for it yes. I am also going to try another spark plug. I have found the coldest I can run is an LTR7ix11
    Head Calibrator
    Gwatney Performance Innovation
    Jacksonville, AR 501-982-2102

  7. #7
    Lifetime Member swingtan's Avatar
    Join Date
    Jul 2007
    Posts
    1,590

    Default

    If it's anything like the E39 SIDI motor, then I think the knock is a "design feature". The only way I could effectively reduce it in mine was to run a 17% ethanol blend (as a test I added about 15L of E85 fuel to the tank). This made a significant difference to power and the knock levels.

    Generally though, I work on the usual fuel and spark tables to tune out the KR. I actually increase the sensitivity settings to try and reduce the audible knock as well.

    If you think you are getting false KR, then look into "Knock Balance Rates" {B1940} in my OS. Any positive value in here has the tendency of adding KR even when nothing is detected. I should do some more work on that table to see if it can be effectively used when tuning, or if it's just a stock OS fail safe for the all encompassing tune.

    Simon.

  8. #8
    Lifetime Member Rhino79's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default

    It is an sidi motor. So for tomorrow I'm gonna swap/read plugs. Go colder if needed. I'll check those tables Simon. I actually bumped the noise threshold up in hopes I would see a change in kr reported but no. I'd like to give the owner an 93 and e 85 tune, but I hate to have to detune it son much if it"may" be false knock.
    Head Calibrator
    Gwatney Performance Innovation
    Jacksonville, AR 501-982-2102

  9. #9
    Lifetime Member Rhino79's Avatar
    Join Date
    Jul 2006
    Posts
    298

    Default

    Another reason for me to believe its false is that the pistons are now 2618 forged and run much more skirt clearance than stock. Nearly .003" more than stock I do believe.
    Head Calibrator
    Gwatney Performance Innovation
    Jacksonville, AR 501-982-2102

  10. #10
    Joe (Moderator) joecar's Avatar
    Join Date
    Apr 2003
    Posts
    27,726

    Default

    If you can, use a listening device (e.g. Chassis Ear) to listen to the block while running on the dyno, real knock will be apparent and distinct from other mechanical noise.

Page 1 of 4 123 ... LastLast

Similar Threads

  1. 2012 Camaro LFX
    By sycraft in forum E39, E80, E82 & E92 SIDI ECM's
    Replies: 13
    Last Post: November 7th, 2012, 08:37 AM
  2. E39 VE Auto Tuning
    By horst in forum E37, E38 & E67 PFI ECM's
    Replies: 3
    Last Post: August 6th, 2012, 06:17 AM
  3. E39 DMA PID's
    By swingtan in forum E39, E80, E82 & E92 SIDI ECM's
    Replies: 12
    Last Post: February 4th, 2012, 08:28 PM
  4. E39 SIDI L4 turbo
    By 3onic in forum E39, E80, E82 & E92 SIDI ECM's
    Replies: 14
    Last Post: January 25th, 2012, 10:54 PM
  5. Auto ve for e39
    By redonetoo in forum E39, E80, E82 & E92 SIDI ECM's
    Replies: 4
    Last Post: June 20th, 2011, 09:15 PM

Posting Permissions

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