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Thread: Sho Boost

  1. #1

    Sho Boost

    I got to take my ski out today....it was almost 70 here....I saw 8lbs of boost...but once I got close to full speed it was reduced back down to 7lbs...this is with the standard charger wheel....

    Soon to have the c3-11....hopefully I will see 10lbs as advertised...

    Also there is no boost produced at all below 5500 rpms is this what everyone else is seeing?


  2. #2
    Whats that whistling noise? jtskier11's Avatar
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    Quote Originally Posted by allstar71 View Post
    Also there is no boost produced at all below 5500 rpms is this what everyone else is seeing?
    Its pretty much a centri. Thats just how they are natured.

  3. #3
    mjh3ides's Avatar
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    Quote Originally Posted by allstar71 View Post
    I got to take my ski out today....it was almost 70 here....I saw 8lbs of boost...but once I got close to full speed it was reduced back down to 7lbs...this is with the standard charger wheel....

    Soon to have the c3-11....hopefully I will see 10lbs as advertised...

    Also there is no boost produced at all below 5500 rpms is this what everyone else is seeing?
    I'm seeing the same thing...mid 70's E temp boost 0'd out @ 6000, and ~5500 in mid 60's temp. I'm also seeing the same reducton in boost...with the stock prop on the 7750 rev limiter I was seeing 8.0 for ~10sec, then it would drop to 7.0. On the 13/23(slightly over-propped) I'm seeing 7.7 @ ~7500rpm then drops to 7.2.

    Have you noticed that when you gradually add throttle the boost tops out .5psi less than if you gun it from the start? I've consistently had this happen, so I'm interested to know if yours does the same thing.

  4. #4
    yeah it was about 65 deg here when I was doing this...I will try slowly adding power next time...however, I think mine is doing the same thing because sometimes it would only get to 7.5 but did not make the connection that you made as to why it was doing it I just thought it was strange...I also have the stock prop...

    I dont think that there is a boost limiter I just think that reducing boost is what it does when it hits the rev limit...we will see soon I have the c3-11 on order

  5. #5
    mjh3ides's Avatar
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    Thanks, I look forward to hearing if yours does the same when gradually adding throttle. I thought it might be my BOV leaking since I haven't tested with the stock SC hose after installing the manifold upgrade, IC spacer & cooling kit. I was also doubtfull of a boost limit, but now I'm well below the rev limit with the 13/23 and it's still doing it after a few seconds @ WOT. I wasn't planning on upgrading my ECU, so I'm gunna be bummed if you can't get more than 7-8psi without one.

  6. #6
    It's not the destination, it's the journey!! Rip'nTear SHO's Avatar
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    It's the limiter......boost limiter...

  7. #7
    Quote Originally Posted by Rip'nTear SHO View Post
    It's the limiter......boost limiter...
    do you see more than 8lbs of boost at anytime with the c1??

  8. #8
    SHOTIME's Avatar
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    is there a way to b.s. the computer into thinking it doesn't have as much boost?!!

  9. #9
    Site Admin Green Hulk's Avatar
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    Quote Originally Posted by Rip'nTear SHO View Post
    It's the limiter......boost limiter...

    RIP is right. Boost is reduced by the "fly by wire" throttle actually closing off at WOT.

  10. #10
    Quote Originally Posted by mjh3ides View Post
    Thanks, I look forward to hearing if yours does the same when gradually adding throttle. I thought it might be my BOV leaking since I haven't tested with the stock SC hose after installing the manifold upgrade, IC spacer & cooling kit. I was also doubtfull of a boost limit, but now I'm well below the rev limit with the 13/23 and it's still doing it after a few seconds @ WOT. I wasn't planning on upgrading my ECU, so I'm gunna be bummed if you can't get more than 7-8psi without one.
    I think that the ecu may allow the high boost up to the rev limit then knock it down...because everyone has reported that with the C1 wheel acceleration is improved...how could this be if boost is not raised? I would think that you will see more boost up to the limit then it will be cut back to 7lbs...

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