Speed Cal or 23 tooth

Discussion in 'Drivetrain' started by Witzy0070, Apr 18, 2015.

  1. Witzy0070

    Witzy0070 Active Member

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    I am getting my 4.30 gears installed this week in my 1996 Cobra. It has the T-45. Using Late Model Restorations calculating tool it says I can use a white 23 tooth gear. However, I am worried it won't be accurate enough. I don't know if it will be, never swapped speedo gears. Does anyone have any input on this matter? Thanks.
     
  2. CC'S95GT

    CC'S95GT Legend

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    I'm not sure about the t45. but on the t5 the 23 tooth gear is only good up to a 3:55. After that you still need a speed cal.
    But that really depends on what's on the trans too. Because the speedo drive gear inside the trans can be changed too. But the tail of the trans needs to be removed to do it.
     
  3. Witzy0070

    Witzy0070 Active Member

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    They're different. From what I know the T5 has a 6 drive gear teeth and my T-45 has 7.
     
  4. lutter94

    lutter94 Well-Known Member

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    Ford Racing Speed Cal is awesome.
     
  5. Ferocious

    Ferocious Legend SN95 Supporter

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    Speedcal. I have a speedo gear in mine and it's off by like 30 still.
     
  6. blackdemon007

    blackdemon007 Active Member

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    This ^
    I also have the 23 tooth, with 4:10 gears and its still off 10 mph at 60.
     
  7. Witzy0070

    Witzy0070 Active Member

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    Damn. Well I will start with the 23 tooth and use a GPS to verify. Either way looks like a speed cal is on the way. I will update this in a few weeks.
     
  8. CC'S95GT

    CC'S95GT Legend

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    If your getting a speed cal, why even mess with the 23 tooth gear you know isn't going to work?
     
  9. lutter94

    lutter94 Well-Known Member

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    ^ this
     
  10. rz5.0

    rz5.0 Legend

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    It's going to be off.. and the 23 gets chewed up..
     
  11. rz5.0

    rz5.0 Legend

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    If it was a t5 it be a different story. .
     
  12. Witzy0070

    Witzy0070 Active Member

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    1. Because I can.

    2. Because 15 dollars is hardly much money.

    3. It takes 5 minutes to install.

    4. Because I don't know for a fact it won't work.
     
  13. rz5.0

    rz5.0 Legend

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    The 23 is also recommended for 410 so...
     
  14. Witzy0070

    Witzy0070 Active Member

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    There is no recommendation for 4.30 gears, the difference between the 4.10 and 4.30s is so minute.
     
  15. Witzy0070

    Witzy0070 Active Member

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    Bottom line, I am going to try the 23 tooth and use a GPS to find the dissimilarities. If I have to use the Speed Cal then I will buy it. I enjoy testing real world function on my own. It's part of why I have a "hot rod".
     
  16. lutter94

    lutter94 Well-Known Member

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    5%. I guess its personal preference if thats acceptable or not. I wouldn't like it.
     
  17. 94yellow50

    94yellow50 Member

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    I have a speed cal on my 94 with 4.10s. Had it with the auto and now the t5. Surprisingly I never adjusted it from when it was auto 3.73 to now t5 and 4.10 and it only reads 3mph fast.