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Wheel size...

Discussion in 'Lifted & Offroad Suspension' started by str8himalaya, Apr 25, 2010.

  1. str8himalaya

    str8himalaya Member

    Whats the biggest size wheel i can put on my stock rim? I would like to put a 285 thats going to fill pretty well on a leveling kit. Was looking at the Cooper Discoverer S/T's. I dont understand how wheel size is calculated as well, any help would be greatly appreciated!
  2. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    Need more info.. But we will assume that you have a 16in rim for this...
    the 285 stands for 285mm (the measured width of the tread face) the 70 is 70% of the tread face is how tall the side wall is from the rim to the tread face. and the 16 is obviously for your rim.. equalling 285/70/16. The same goes for a 205/60/14 etc etc.... Now if you have a 7in rim generally you can fit up to a 305 as far as i understand. So i hope this helps you out. And i wrote this clearly enough since sometimes my mind outruns my typing.
  3. str8himalaya

    str8himalaya Member

    That helps greatly actually. I have the aluminum alloy wheels with the chevy wheels on it. What size width would the stock rim be?
  4. str8himalaya

    str8himalaya Member


    A 7 inch wide rim=177.8 mm? Thats the conversion i got, how would that relate with 305?
  5. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    The bead will still seat with the tire bowing out from the rim. And as for rim widths i am not 100% on how they handle that part. Since the 7in usually is just the rim with out the bead.
  6. str8himalaya

    str8himalaya Member

    Well i just measured my current tire and it is about 8 inches across. That only comes out to 215? Hopefully i can fit something much bigger than that?
  7. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    The thing that you are forgetting to add is the roll of the tread face.. I dont have a pic to show you how it works but there is a place that the tread face, and the sidewall meet. THat is how it is all measured.. Plus you can actually take some of the width plus or minus for each manufacturer since there can be variances in width for each one.
  8. str8himalaya

    str8himalaya Member

    Ah so you also have to add in the space between the rim and the start of the tread. The more space, the tighter it will hug the wheel well. That makes since.
  9. murdog94

    murdog94 Epic Member 5+ Years 5000 Posts

    that is where the 70 comes in.. 70% of the tread face.. Steping up to a 75 will add another 5% of side wall..
  10. str8himalaya

    str8himalaya Member

    So you think the biggest i could go is 305/75/16?

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