Guys I have tried the search facility without joy as I know there are lots of threads concerning wheel/tyres. Does anyone know the rules concerning rim size versus max tyre size. For instance, How wide can you safely go with a 7.5J rim or an 8J rim etc. Is there a standard calculation that can be used. Thanks
yes and no. But the "j" doesn't matter. It's just the 7", 7.5", 8" width of the wheel itself. some links to help out: http://www.tirerack.com/tires/tiretech/general/size.jsp http://www.tirerack.com/tires/tiretech/general/size_information.jsp http://www.tirerack.com/tires/tiretech/general/size_conversion.jsp great calculator (but for Miata's primarily) here: http://www.miata.net/garage/tirecalc.html but keep in mind, the most important aspect of buying different tires, even if they are the same sizes, brands/models will differ. For example, for my car, an [Honda] OEM Potenza S02 in 225/50/16 will be much wider than a Pole Position Potenza S02 (which is discontinued btw) of the same size. An OEM tire can be shaped differently and treaded differently.