Scott, what is the tire size on the Miata?
You might consider getting tires with higher sidewalls. A higher sidewall makes a big difference in a Porsche 914, which is very similar to the Mazda Miata in terms of body size and weight. A 60 sidewall is a good compromise between comfort and handling, and a 65 sidewall would be very comfortable but of course the handling (cornering) would not be crisp. Many people opt for the comfort of a 65 sidewall. Whatever keeps your lady happy.
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