Speedo: How off with 33s?

Discussion in '100-Series Cruisers' started by macneill, Nov 1, 2005.

  1. macneill

    macneill Rollin’ on 33s

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    What is difference in mph with 33s?

    Not that Grandpa here rarely goes above what I think is 65, but was just wondering how off it is.
     
  2. spressomon

    spressomon glutton Moderator

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    Mac,
    With my 285R75 16 GY MT/R's the actual difference (GPS) is 5%. So at 65mph the actual speed is 68mph (actually 68.25).
     
  3. macneill

    macneill Rollin’ on 33s

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    Ahhh... very good. Thanks.
     
  4. mheredia2930

    mheredia2930

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    I had mine checked a few years back, but I remember that there was a 12-13% difference with my FJ60. I have 33x12.5x15. So when it shows 65mph on my speedometer, I am actually going about 75mph... Hope this helps..
     
  5. hoser

    hoser SILVER Star

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    If one didn't have a GPS...

    33"/31.3"=1.05
    A 5% increase given the speedo is accurate in the first place.
     
  6. ShottsUZJ100

    ShottsUZJ100

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    33 = 5%
    35 = 12%
     
  7. spressomon

    spressomon glutton Moderator

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    Remember "31", "33" etc. is nominal dimension...ultimately the actual circumference may differ slightly for each brand/model of tire.
     
  8. Cruiser_Nerd

    Cruiser_Nerd That 25 Guy. Moderator

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    This would make sense, as I think stock tire size on the 60 was a 235/75/15 The 100 would be seeing a smaller difference because of the taller OEM tire. :)
     
  9. tabraha

    tabraha Hello My Name is: TAD SILVER Star

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    Pretty much what I get too when I have the 285/75R16 Revo's on.
     
  10. tabraha

    tabraha Hello My Name is: TAD SILVER Star

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  11. NMuzj100

    NMuzj100

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    5.4% difference for 285/75R16 vs the 275/70R16 stock tires. YMMV
     
  12. Landpimp

    Landpimp GOLD Star

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    285's.

    60 on the spedo is 64 on the GPS...............I don't do math :D
     
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