185/65x14", 195/55x15" are stock sizes for most Civics. So the next size would be 205/45x16" to keep your speedo accurate. You could go with 205/40x16" but potholes would suck, the ride sucks, and your speedo will be off.
Just to show with my stockers on at 80mph my rpms are 4000rpms. With my 215/40x16" on at the same speed my rpms are at 4500rpms which is a bit LOUD! :0
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