Hmmmkay. If you want performance you should get 17s but that is up to you.
8.5" +30 sounds good at the rear, it is the exact same width and offset that I am using . It will require guard rolling though with a 235 tyre and conservative camber.
At the front I think you could go a little wider if you are not worried about being unable to rotate tyres from front to rear. A 9" wide wheel with +30 offset should fit pretty well with a 255 tyre and not too much camber but if you don't want to run camber go with closer to +40. I am not sure what your options are in tyres though for 18" wheels but 255/40 17 is a very common size if you elect to go with 17s.
You might find it easier to decide what tyre sizes you want to run first and then work backwards from there. That is how I decided on my rims.
8.5" +30 sounds good at the rear, it is the exact same width and offset that I am using . It will require guard rolling though with a 235 tyre and conservative camber.
At the front I think you could go a little wider if you are not worried about being unable to rotate tyres from front to rear. A 9" wide wheel with +30 offset should fit pretty well with a 255 tyre and not too much camber but if you don't want to run camber go with closer to +40. I am not sure what your options are in tyres though for 18" wheels but 255/40 17 is a very common size if you elect to go with 17s.
You might find it easier to decide what tyre sizes you want to run first and then work backwards from there. That is how I decided on my rims.
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