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Is my math correct? This tire size MINUS an inch...?

Discussion in 'Wheels & Tires' started by Springthing, Apr 7, 2009.

  1. Springthing

    Springthing New Member

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    I am trying to get from one tire size to get an inch thinner tire. Please tell me if I have the math correct:

    305 70 16 is what I have on. I want to get an thinner tire because of some slight fender rub. Please tell me if I have this correct:


    305 70 16 = 33 x 12.01 x 16

    12.01 - 1 = 11.01

    33 x 11.1 x 16 = 285 75 16 (actually 280 77 16)


    So putting a 285 75 16 tire on my 10 inch rims should decrease the width of the tires by 1 inch, correct?


    Anyone?



    Bonus question: I should be able to go one inch thinner still with a 16 x 10 rim, right? Will that give me too thin a look?
    #1
  2. pmf608

    pmf608 New Member

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    Yes, this is as close to one inch as you will get. The only numbers you need to look at for width are the first series - 305 and 285. These are in millimeters, and each inch is 25.4 millimeters. A 20mm decrease is a bit over 3/4 of an inch. going down to a 275 would be slightly over an inch. Long story short. Your calculation was one of the 2 closest sizes. You should be able to stick with the 10 inch rim, without looking too narrow. hope this helps
    Last edited: Apr 7, 2009
    #2
  3. Mindi51982

    Mindi51982 New Member

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    Go back to school :lol::great:
    #3
  4. CarpenterGuy

    CarpenterGuy New Member

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    a kid at my school has 285/75/16's. his are thinner than my old trucks 33x12.5's. i'm sure it'll work for you.
    #4
  5. Pete95Sierra

    Pete95Sierra New Member

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    it will work fine. the 285 tires are usually more like 11.5 inches wide and on the 10" wide rim they will look good. If you want to see what a 285 looks liek ona 16x8 rim look at my pics, that is the setup I ran
    #5
  6. 95CTburb19

    95CTburb19 New Member

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    285's should be fine :great: Throw the 305's on craigslist, I bet they'll sell pretty quickly.
    #6
  7. Springthing

    Springthing New Member

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    Thanks for all the input. That's what I'll do then.

    Mindi- unfortunately they didn't teach tire size mathematics in my school! lol
    #7

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