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Sumitomo T4 195/65R15 vs. GPS

Discussion in 'Gen 3 Prius Technical Discussion' started by bwilson4web, Aug 16, 2010.

  1. bwilson4web

    bwilson4web BMW i3 and Model 3

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    After a second flat in the repair area of a tire, I replaced all four with Sumitomo T4 195/65R15, Toyota had a sale. But I notice the GPS distance does not match the tripmeter distance:
    Column 1 Column 2
    0 miles source
    1 102.6 GPS
    2 102.1 A trip meter
    Assuming the GPS is accurate:
    0.5/102.6 ~= 0.5% error
    ​
    Bob Wilson
     
    #1 bwilson4web, Aug 16, 2010
  2. cproaudio

    cproaudio Speedlock Overrider

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    Of course the GPS will show farther distance compared to the tripmeter. The OEM tire is 195/65/15 not 195/70/15. This means that the tires you replaced has larger OD and less rotations per mile than the OEM size. Did you buy a 70 series tires for correcting the speedometer's reported speed error?
     
    #2 cproaudio, Aug 16, 2010
  3. xs650

    xs650 Senior Member

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    Scandalous:D

    Good news is after you have worn 2/32 off your tread, your odometer will be perfect. :rockon:
     
    #3 xs650, Aug 16, 2010
  4. bwilson4web

    bwilson4web BMW i3 and Model 3

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    Correction, I wrote the wrong tire spec:

    195/65R15 - ZVW30
    195/70R14 - NHW11, a different experiment

    Regardless, tire wear should bring them smack dab perfect someday in the future.

    Bob Wilson
     
    #4 bwilson4web, Aug 16, 2010
  5. adrianblack

    adrianblack Member

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    On a regular Gen III does GPS speed match the CAN speed? I seem to recall it does on my car .... and am pretty bothered by the fact Toyota artificially inflates the digital speed display.

    You will have slowed down acceleration with the bigger tires. :)
     
    #5 adrianblack, Aug 18, 2010
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