Engine Drivetrain 2nd Gen S Most liked posts in thread: Boost gauge question

  1. Redbeard

    Redbeard JCW: because fast is fun!
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    #2 Redbeard, May 23, 2012
    At idle (when warm) the engine ocillates a few revs about once a second or so. It's small, 50-75 rpm, not so much as it will show clearly on the tach (because it is electronically smoothed) but if you listen to your exhaust you will hear it. That flux can easily account for the 2-inches of mercury you are seeing move in your boost gauge which has no e-nanny smoothing it out.

    When it's cold it will tend to be steady.

    18-20 in-Hg at idle when the car is warm is exactly where it should be. 14 psi is about right for max "overboost". Sounds like you are running well.
     
  2. Metalman

    Metalman Well-Known Member
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    #7 Metalman, May 31, 2012
    ^^^I used the "Push to Connect" tube fittings with my BSH tap..... They come with a thread sealant already on the threads. The fitting has a built in gasket that seals onto the tubing. There is even a bulkhead fitting that allows you to pass the tubing through the firewall. You press the black ring and the tubing pulls away from the fitting. Easy Squeezy.....:D
    [​IMG]
    McMaster-Carr
     
  3. grodenglaive

    grodenglaive New Member

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    #3 grodenglaive, May 23, 2012
    ah thanks. Yeah it doesn't register on the tach, but I can hear it. It seems to be more pronounced now that I can see it on the gauge - probably psychological.:crazy:
     
  4. SacredDisorder

    SacredDisorder Because Race Car?
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    #4 SacredDisorder, May 29, 2012
    Is the car an Auto or Manual?
     
  5. DneprDave

    DneprDave Well-Known Member
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    #5 DneprDave, May 29, 2012
    I have a mechanical Marshall boost gage, with a BSH dual boost tap, in my MINI, it is steady at idle.

    Dave
     
  6. grodenglaive

    grodenglaive New Member

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    #6 grodenglaive, May 31, 2012
    it's a manual. It turns out I have a leak where I connected the boost gauge line to my BSH dual boost tap. It got worse and I started loosing boost pressure as well - wouldn't go over 2 psi. I bypassed the gauge and was back to full turbo power.
    Now I put some teflon tape on the threads where the gauge line screws into the BSH tap. It was OK for awhile, but returned at an autox event on Sunday. I think I will remove the BSH tap and start over. Wish I had gotten the electronic gauge instead:mad2:
     
  7. grodenglaive

    grodenglaive New Member

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    #8 grodenglaive, May 31, 2012
    oh yeah, those are awesome!