http://clubs.hemmings.com/clubsites/chevylist/tech/tire_size_conversion.htm (http://clubs.hemmings.com/clubsites/chevylist/tech/tire_size_conversion.htm)
cool here is another good one
http://www.therangerstation.com/tech_library/Metric_To_Inch_Tires.html (http://www.therangerstation.com/tech_library/Metric_To_Inch_Tires.html)