User Tag List

Results 1 to 7 of 7

Thread: Backfire when you dump the boost

  1. #1
    Join Date
    Aug 2010
    Location
    West Pennant Hills, Sydney NSW
    Posts
    261

    Default Backfire when you dump the boost

    I have recently been getting a backfire when I take my foot of the peddle, always when boost is being dumped never when there is no boost (low revs).

    I have reconnected the entire system from the air filter through to the inlet to the engine, all claps are done tight, no air leaks. (this has been on another post =backfire on gear change)

    At the moment the guys (thanks tons to Jmac and Robmps) have helped diagnose that its the GFB BOV that is causing the MAF to read wrong and run rich.

    The link below is to some logs I put in the dropbox account.
    https://www.dropbox.com/sh/714ck1zt4zpjr9i/5Ild1rjnNg


    The last log had a backfire the first 2 (log 7 and 8) are just cursing to get a general feel of how the care is running in traffic. Log 9 has the backfire as I am driving with the foot a little heaver to get the boost up.

    Anyone know a way around the BOV issue? I will put the stock on in the mean time so I don't damage the engine. sucks that its the GFB one too, I realy wanted to support Australian products. (although thats the only one )

    thanks guys
    Tim
    __________________________________________________ ________________________________________________
    CorkSport SRI-TIP ][ KingSprings ][ CP-E TMIC][ Cobb AP (stage 1 tune) ][ Prosport Boost gage ][ Apexi RSM, ][corksport top front strut brace ][ corksport top rear strut brace ][ corksport short shift plate ][ Autotech HPFP internals ][ CS LED light kit ][ CS rear engine mount][CSDP ][ GFB BOV ][DBA front disks]

  2. #2

    Default

    I haven't looked at the logs, but I think you mentioned in the other thread that you basically bolted the BOV up straight out of the box.

    In the instructions for the BOV, it said to 'tune the spring pressure' after install. Basically involves turning it to full atmo, giving the throttle a few good stabs and watching the piston close, then adjusting the spring pressure accordingly.

    Maybe give this a shot to see how it works? (Have attached the instructions in case you haven't seen them before).
    Attached Files Attached Files

  3. #3
    Join Date
    Nov 2008
    Location
    North side, Vic
    Age
    37
    Posts
    6,745

    Default

    Only had a few minutes to review but the HPFP looks fine, 11,xxx kPA through acceleration.

  4. #4
    Join Date
    Aug 2010
    Location
    West Pennant Hills, Sydney NSW
    Posts
    261

    Default

    Quote Originally Posted by Jamesa2z View Post
    In the instructions for the BOV, it said to 'tune the spring pressure' after install. Basically involves turning it to full atmo, giving the throttle a few good stabs and watching the piston close, then adjusting the spring pressure accordingly.

    Maybe give this a shot to see how it works? (Have attached the instructions in case you haven't seen them before).
    Thanks mate I appreciate that. I have been adjusting it and it seemed to lesson the severity of the backfire, but to be honest I was trying multiple fixes at once, adjusting that and working on hose clamps, re flashing the tune etc... Now that the BOV has been more or less identified as the issue I can focus more on getting it to work better. As of today (vented to air a little, 20/80) it seemed better, but it was hot and I didnt punch it to much. will adjust and try it out tomorrow.
    __________________________________________________ ________________________________________________
    CorkSport SRI-TIP ][ KingSprings ][ CP-E TMIC][ Cobb AP (stage 1 tune) ][ Prosport Boost gage ][ Apexi RSM, ][corksport top front strut brace ][ corksport top rear strut brace ][ corksport short shift plate ][ Autotech HPFP internals ][ CS LED light kit ][ CS rear engine mount][CSDP ][ GFB BOV ][DBA front disks]

  5. #5

    Default

    you will get backfire when venting to atmo as the metered air is no longer there but extra fuel was already added. if its easy to change from vta to recirc, try fully recirc to see if the backfire dissappears.

  6. #6
    Join Date
    Jun 2012
    Location
    Sydney
    Age
    40
    Posts
    1,062

    Default Backfire when you dump the boost

    Man it's not that big of an issue, mine does it from time to time, give Brett a call from GFB he is a great guy and will tell you how to minimize of eliminate backfire but really the logs look fine so just a little lost fuel is about all the harm your going to cause, a BOV will not damAge your engine.

  7. #7
    Join Date
    Aug 2010
    Location
    West Pennant Hills, Sydney NSW
    Posts
    261

    Default

    Quote Originally Posted by Robmps View Post
    Man it's not that big of an issue, mine does it from time to time, give Brett a call from GFB he is a great guy and will tell you how to minimize of eliminate backfire but really the logs look fine so just a little lost fuel is about all the harm your going to cause, a BOV will not damAge your engine.

    thanks Rob, thats good to hear. Ill give Brett a call, I spoke to him prior to buying the BOV. thanks again for the input, I appreciate the advice guys. these forums are brilliant!
    __________________________________________________ ________________________________________________
    CorkSport SRI-TIP ][ KingSprings ][ CP-E TMIC][ Cobb AP (stage 1 tune) ][ Prosport Boost gage ][ Apexi RSM, ][corksport top front strut brace ][ corksport top rear strut brace ][ corksport short shift plate ][ Autotech HPFP internals ][ CS LED light kit ][ CS rear engine mount][CSDP ][ GFB BOV ][DBA front disks]

Posting Permissions

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