User Tag List

Page 2 of 2 FirstFirst 12
Results 21 to 30 of 30

Thread: Xede as Boost Control

  1. Default

    OK, from Lachlan and Rob:-

    (I really hope this doesn't confuse everyone even more)

    The ECU will learn "closed loop fuel trims" in "closed loop mode" - We all, (I think) understand that one. These trims are also applied in "open loop" once learned, even at full throttle. It normally only takes 20 seconds to a minute of engine running at each RPM and load point to learn the trim values. This can make the tuning a little more difficult and time consuming and a DH or good scanner is part of the tuning regime as much as a good dyno.

    Aside from those fuel trims, the ECU will also "learn" to achieve a "specific airflow" which really is a "specific power" level in our terms. If the expected airflow target is not met, the ECU will increase boost pressure to try and achieve it. There are many additional bounds in the ECU to stop it learning too much boost at certain RPM etc.

    So, as well as learning fuel trims, the ECU can "learn" different boost pressures based on the airflow signal (and hence the air temperature and pressure) per RPM and per Gear. Tuning with this many parameters can be a little complex and changes in boost pressure are expected depending upon current ambient conditions of air temperature and pressure. The "boost spike" is only a problem if it takes the turbo outside of its critical operating envelope to a point where premature failure is likely. The nature of the (good) boost control system is to get boost in (relatively) as fast as possible and then control the boost quickly after reaching a target value.

    It is difficult for ChipTorque to comment further and we have discussed directly with Crusher_13 that we'd like to see some dyno graphs, data and a copy of his XEDE's tune so that we can assist further.
    follow us on twitter - http://twitter.com/chiptorque

  2. #22

    Default

    No boost issue from the flash tune, or since the XEDE was fitted for that matter.

    My boost issues come from the turbo that's fitted.........

  3. Default

    Leah, Lachlan and Rob,

    Thanks for the reply. That works with what my tuner and I figured.

    As I told Lachlan on the phone we have decided to sit tight for a couple of weeks and hope it sorts itself out. With any luck and a couple of hundred kms all will be sweet and I can post up some nice numbers for Chiptorque.

  4. #24

    Default

    there's nothing wrong with setting a MBC up .. setting it to 18.., then tuning around it.. at least then you know youll have no spike.. and it will be a rock solid boost pressure.

    Been done in the states for a while.. with good success, as long as your using a quality MBC..

    Hit me up if you want to know more about this.. otherwise ill just shut up..

    Doc

  5. Default

    Thanks Doc.

    Will put her back on the dyno hopefully in the next week or so work permitting and go from there.

  6. #26

    Default

    ok.. if you do go the MBC with the Xede.. (my personal recommendation.. especially with the upgraded TMIC)
    get your hands on one of these..check the link:
    Boost Controllers

    The second one from the top.. high performance boost controller. Utilizing a uniquely engineered ball/spring mechanism combined with an adjustable bleed valve, this MBC allows you to spool your turbo faster and the adjustable bleed mechanism lets you minimize the massive boost "spike" that can occur with poorly designed ball/spring manual boost controllers, or factory boost controllers working outside their designed range.

    This is the exact MBC woosh used and recommended from memory.

    Ive heard and read nothing but good things about them..
    I may almost think about getting one and setting it to 16. But im still not sure.. Im having fun spending other peoples money

    ---------- Post added at 10:22 PM ---------- Previous post was at 10:17 PM ----------

    Check this

    look how fvcking good my boost holds - Mazdaspeed Forums
    Last edited by Doc; 21-04-2010 at 10:40 PM.

  7. Default

    I will be booking her in for a new tune in the next two weeks or so.

    I have ordered a MBC just incase and at $129 I think it is money well spent. If I need it I need it, I don't I don't.

    I am hopeful that I won't need it as my car seems to have lost some power recently, the induction noise is quiet, and the 2nd gear acceleration has calmed. I am hopeful that the ECU has learnt what is going on and has made some adjustments.

  8. #28
    Join Date
    Nov 2008
    Location
    NSW
    Age
    47
    Posts
    789

    Default

    Its gotta get pretty annoying spending a fair bit of cash on almost every bolt on mod possible & then feel like your car is loosing power.....maybe you are just getting used to it. Hopefully the tune will sort it out. The factory ECU is definately a PAIN IN THE ASS !!!!!!!!!!!!!!!!!!!!!!!!!!!!!

  9. Default

    With any luck I will be getting a second car soon to strip and track...

    That should be interesting.

    Chiptorque - Xede or Ezyflash best for a bug eye WRX?

  10. Default

    Ezy-FLASH Pro for +MY01 WRX's. Licenced Tuning software is nearly complete for Ezy-FLASH Pro, so you can get this tuned locally if needed. Or email your Ezy-FLASH Pro high speed logs back to ChipTorque for Tune assistance.

Page 2 of 2 FirstFirst 12

Posting Permissions

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