putting new wheels on... overall diameters within .4 of an inch - speedo affected?

Discussion in 'OT Driven' started by Jay487, Mar 26, 2008.

  1. Jay487

    Jay487 What's Life If You Ain't Enjoyin' It?

    Joined:
    Dec 11, 2001
    Messages:
    4,126
    Likes Received:
    0
    Location:
    Syracuse, NY
    I have 205/60/15 tires on my 98 camry right now, replacing with 225/40/18...

    I used pepboys overall tire diameter equation (HERE)

    and the overall diameter with stock wheels and tires comes out to 25.49.
    The new wheels and tires come out to 25.09.

    How much will my speedometer be affected?
     
  2. hypntyz

    hypntyz OT Supporter

    Joined:
    Feb 9, 2004
    Messages:
    8,164
    Likes Received:
    8
    Location:
    east of Knoxville TN
  3. deusexaethera

    deusexaethera OT Supporter

    Joined:
    Jan 27, 2005
    Messages:
    19,712
    Likes Received:
    0
    What really matters isn't diameter, it's rotations per mile. If the rotations per mile are the same, the speedometer will be correct.
     
  4. Silver 93 Supra

    Silver 93 Supra Social Liberal, Fiscal Conservative

    Joined:
    May 5, 2005
    Messages:
    1,099
    Likes Received:
    0
    Your speedometer will be 1.6% to slow. If you go with a 215/40/18 it will only be off .35%
     

Share This Page