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Tuning for the 200mph speedometer?

Discussion in 'Engine/Tuning' started by PaleRider, Jul 4, 2008.

  1. PaleRider

    PaleRider Death Spank Established Member

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    I have a 200mph overlay, Advantage III and stock 3.55 rear gears. What do I need to do to my tune so that the 200mph speedo reads correctly?
    Thanks
     
  2. About2bite

    About2bite SVTNProgress Established Member

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    They really have those?

    :pop:
     
  3. EvilTwins

    EvilTwins I can't find my pulley! Established Member

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    I also have one but I haven't bothered installing it yet.

    I haven't heard anyone speak of how it is done but I was figuring you can probably get it to read correctly by modifying the vehicle tire size parameter using a handheld tuner like an xcal 2. It could even be a trial and error process until it was right (using another car or even better a GPS unit as your guide).

    Not too sure really..
     
  4. rocket5979

    rocket5979 Member Established Member

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    I have never personally done this particular mod but I pretty much figure the way to tune for it would be to first figure for your correction factor. Take that 200mph number and divide it by your current max speedo number (will vary with the car) which will net you the correction factor. Then go into the tire_revs_per_mile in the tune and multiply it by your correction factor. That should get it. Verify with a GPS or a buddies car running next to you. Good luck.
     
  5. PaleRider

    PaleRider Death Spank Established Member

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    Speedhut has them. Mine looks almost stock, which is what I was wanting.
     
  6. PaleRider

    PaleRider Death Spank Established Member

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    I currently have a 160mph speedo = correction factor of 0.8; I hate to have to install it and play around with it to get it to work. I guess we'll give it a try. Thanks

    I remember reading something MileHiDyno said to use the gear table in the Predator to recalibrate the speedo. I don't have a Predator I have the Xcal2
     
  7. rocket5979

    rocket5979 Member Established Member

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    Your correction factor/multiplier should be 1.25......200/160= 1.25. Sorry if I didn't word my last post too well. If you use the .8 like you want (160/200= 0.8) then it will become the divisor rather than the multiplier. Hope that explains it.
     
    Last edited: Jul 5, 2008
  8. PaleRider

    PaleRider Death Spank Established Member

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    My tire_revs_per_mile is 806 so 806 X 1.25 = 1007.5 That's a BIG tire!
     
  9. rocket5979

    rocket5979 Member Established Member

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    Actually if you were to take that 1007.5 figure at face value that would be one SMALL tire. Now obviously for your purpose you will not look at this number in a literal fashion anymore because it is scaled from your correction factor.
     
  10. KONA BLUES

    KONA BLUES HORSEPOWER JUNKIE Established Member

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    You can PM Hissman on this topic. He has a thread or a reply somewhere in the Terminator Talk section regarding the 200MPH overlay from Speedhut.

    He verified the accuracy of his with some type of GPS device from the Military. While it isn't quite EXACT, he has it dialed in close enough ;P.

    At any rate, let us know what you end up using to calibrate yours :beer:


    DORF
     
  11. rocket5979

    rocket5979 Member Established Member

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    Calibrating something like this should take no real effort at all if you know your way around the Advantage tuning even a little bit. I bet that the math I posted will get you real close. Then if you want to you can dial it in further from there. Overall I would consider this would probably be something that anyone with even a little DIY aptitude should be able to do. It cannot be too hard. After all, it is just a gauge overlay install and simple recalibration. I bet once one of you guys tackle this job you will be amazed at how simple it turns out to be. Good luck fella's. :beer:
     
  12. PaleRider

    PaleRider Death Spank Established Member

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    Understand, just being sarcastic.
     
  13. rocket5979

    rocket5979 Member Established Member

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    Ok I gotcha. :beer:
     

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