if you're looking for a more rounded sidewall a 225 will give you that. I went from 225 to 245 on the fronts like many do and and my tires definitely look more "fat" even w/ the lower profile ratio. Remember, its 225/40 is 40% of 225 (90mm) and 245/35 is 35% of 245 (85.75mm).
personal opinion? it will definitely be more rounded
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