airbox deleted 950SE

Discussion in 'Crazy-Awesome almost Dakar racers (950/990cc)' started by buzybraza, Jan 31, 2013.

  1. dogsslober

    dogsslober No neck tie, Ti neck

    Joined:
    Feb 10, 2009
    Oddometer:
    1,101
    Location:
    Morgan Hill Ca
    Thats not that daring:lol3
    #21
  2. buzybraza

    buzybraza Been here awhile

    Joined:
    Feb 28, 2010
    Oddometer:
    387
    Location:
    Escondido, CA
    So because I only cut about half the stacks I get more grunt and more top end! :lol3
    #22
  3. pdxmotorhead

    pdxmotorhead Been here awhile

    Joined:
    Mar 4, 2012
    Oddometer:
    843
    Location:
    Portland OR
    Based on my working on sprints and midgets, the key thing is the stacks move the power band, long stacks make the power peak at lower RPM shorter ones at higher RPM.. Smaller diameter stacks raise torque, larger diameter stacks increase horse power at higher pm (To a point its not magic...) You have to balance runner length against diameter.

    Typically you put the engine on the dyno and test say 4 sets of stacks ,, Map their performance, then you use the set that keep the motor on the power band at the RPM's the track demands of the car to keep it at speed.

    Dave
    #23
  4. pdxmotorhead

    pdxmotorhead Been here awhile

    Joined:
    Mar 4, 2012
    Oddometer:
    843
    Location:
    Portland OR
    Here is something that's close to the same idea..
    this is a standard 32/36 Webber on a Nissan 1600.

    http://www.flickr.com/photos/33629139@N08/8439460347/in/photostream

    http://www.flickr.com/photos/33629139@N08/8440552766/in/photostream

    http://www.flickr.com/photos/33629139@N08/8439460949/in/photostream

    Fairly stock motor with headers, NISMO camshaft.

    The engine was only making consistent power between 4000 and 5000 with the webber alone.
    The velocity stacks lifted the whole power band and pumped the engine up nicely from 2500 to 4000, netting a really race-able power band from about 3000 to 5500 rpm.

    I included the filter pics for reference since its similar to the rottweiler.

    Cheers.

    Dave
    #24
  5. Mosseltje

    Mosseltje Alive

    Joined:
    Apr 17, 2008
    Oddometer:
    224
    Location:
    The Netherlands
    Short Answer: Yes

    Long answer: Below a movie about my SE through the woods after heavy rain.
    My SE has the MotoHooligan airbox (and a very old and weak battery.)
    At 6:14 minutes the puddle is too deep and it killed the engine.

    https://www.youtube.com/watch?v=goJWXDOtRQc
    #25
  6. ata

    ata expat in the jungle

    Joined:
    Sep 4, 2007
    Oddometer:
    2,296
    Location:
    Bilbao, close to the fu****ng Guggenheim
    that frame looks too clean

    seems never suffered too much mud:lol3, or you are just the number one cleaning it



    good work anyway and agree about the amazing performance without air box, looks like the bike´s in a hurry all the time, but here where I ride, ain´t an option
    #26