Page 1 of 2 12 LastLast
Results 1 to 10 of 15

Thread: MAP/Baro sensor on XB Mod help

  1. #1
    Junior Member
    Join Date
    Jul 2018
    Posts
    3

    MAP/Baro sensor on XB Mod help

    Hi Bueller, I'm interested to add a MAP/Baro sensor on my Uly MY2010.
    Buelltooth propose a Baro kit for XB but my idea is to use a 1125 stock bosch MAP sensor.I already have it.
    I understood that need to add one pin at gray ECU connector and enable this mod by ecmspy.
    Anybody already do it or know how to do?
    Thanks for help.

  2. #2
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,846
    Why?

    Your ECM will compensate for altitude already by reading what the engine is putting out (O2 sensor). Thats why they don't need a baro stock.

    And a baro (pressure) sensor is not a MAP (vacuum) sensor unless it's meant for a turbo (the one you happen to have is not).

  3. #3
    Quote Originally Posted by npetra View Post
    but my idea is to use a 1125 stock bosch MAP sensor.I already have it.
    I understood that need to add one pin at gray ECU connector and enable this mod by ecmspy.
    Been there, done that. Don't remember, which of the sensors off a 1125 I used, but it was a stock Bosch PS-AA sensor. I installed it in the rear side of the airbox base. Using the sensor from the 1125 is the easiest way, as you can copy all baro data from the 1125's ECM. Baro correction is more accurate than AFV adjustment and it worked fine. AFV will be stable even on altitude changes, if baro correction is configured correctly.

  4. #4
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,846
    Hey Gunter, how does the 1125 MAP read pressure? Is atmospheric pressure change so small we're lucky it just happens to have that amount of range

    I can see how adding a baro would allow the AFV to stay in place, because the ECM would add a global baro modifier to the chain, not relying on the global AFV modifier to do that small adjustment.

    So whats the difference? Why add something else to the chain? Because even though a baro modifier would be simple to write, it's still the hammer of a global map change (just like AFV).

    You're the Master, what am I missing?

  5. #5
    Senior Member
    Join Date
    Mar 2015
    Location
    Phoenix, AZ
    Posts
    1,238
    Doesn’t the Buelltooth guy offer this mod as a kit?

  6. #6
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,846
    I dunno? I'm still unclear to what the advantages would be.

    No ones riding up and down in elevation faster than the AFV could compensate. I really hope gunter gives an answer, I'm super curious

  7. #7
    Senior Member
    Join Date
    May 2014
    Posts
    633
    >>>>Doesn’t the Buelltooth guy offer this mod as a kit?
    >>Buelltooth propose a Baro kit for XB but my idea is to use a 1125 stock bosch MAP sensor.I already have it.


    1125 utilizes separate MAP and Barometric pressure sensors. They are identical parts.
    A MAP sensor can work with the 45 deg. v-twin design but needs the proper engine management algorithm.
    Even the H-D Sportster has a MAP sensor (combined with IAT), and dual O2. But different ECM than Buell.
    And the 1125 has different intake pulse timing as a 72 degree v-twin.

    >>So whats the difference? Why add something else to the chain?
    It's the same reason that fueling adjustments are made for IAT, ET, and even battery voltage.
    Also, we don't have short-term and long-term fuel trims for each cell, so dynamic modifiers such as Baro can help.

    Ideally, the base fuel map itself would be auto-adjusted over time (trims) based on O2 feedback.
    With a static map, even O2-driven closed loop is not perfect. For example, when TPD and/or RPM change, ECM moves to another fuel lookup table cell. If that cell value is way off for the actual needed runtime condition - let's say too lean, it takes time for the ECM to increase fueling to get O2 voltage back to the middle. It does this incrementally by increasing pw in steps; it doesn't happen instantly. During the time taken, performance and rider experience could be affected.

  8. #8
    Junior Member
    Join Date
    Jul 2018
    Posts
    3
    ReadyXB I agree with you and for those reasons I would like to add a air pressure sensor.
    Another reason is try my Uly in open loop so MAP sensor are mandatory.
    I live in sicily, near Etna volcano, so in 20min I can start from sea level to 2000m altidude and over...

    So any idea, suggestion to implement bosh MAP sensor to XB?

  9. #9
    Senior Member Cooter's Avatar
    Join Date
    Dec 2012
    Location
    Crawling up your skirt
    Posts
    6,846
    ReadyXB: Are you saying that adding an air pressure sensor (Baro or 1125 MAP) with the proper algorithm can make the adjustments to mixture (injector pw) faster than regular EGO or AFV adjustments? and enough to notice? I'm honestly surprised by that. I have experienced what lots of bad tunes do (my bad) and CL makes adjustments pretty dang quickly.

    Theres a separate "airbox pressure sensor" that can be enabled. Wouldn't that be even better to use the sensor inside the airbox? Seems to me the same exact Baro algorithm could be used in there.

    npetra: Yes, if your intention is to dis-allow the ECM to make changes by running Open Loop only, a Baro of some kind is necessary. I'm sure you can use the 1125 MAP if gunter says you can The trick is to get the right algorithm for that sensor from a stock 1125 tune. OR buy the cheap Baro kit from Buelltooth that comes with the proper algorithm for that sensor.
    That sounds like a much easier idea than using the 1125 MAP sensor just because you have it?

  10. #10
    Quote Originally Posted by Cooter View Post
    The trick is to get the right algorithm for that sensor from a stock 1125 tune
    http://www.ukbeg.com/forum/viewtopic...o+corr#p280706



Page 1 of 2 12 LastLast

Posting Permissions

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