A number of thoughts:
First, going from 195/75R14 to a 165/65R14 is going down 5 sizes! Not only is that totally unsafe, but your fuel economy is going to be hurt. Stick with the original size - and if anything, go
UP!.
Second is that while measuring a tire's free standing diameter (that is, unloaded) as opposed to the loaded radius is the right way to do revs/mile, there is 3% factor that needs to be inserted to get the actual rolling circumference (or rolling diameter).
Put another way: If you are using the actual tire circumference, the rolling circumference is 97% of that value.
Why? I'm not sure, but I think this has to be with the belt acting like a tank track - that the effective length of track would be analogous to the circumference of the belt, and it doesn't matter how much tread is on the tire, the rolling circumference is controlled by the diameter of the belt (except we do know that tread depth plays a role in the revs/mile, so this explanation doesn't quite work.) Whatever the reason is, if you look at the tire manufacturer's values they have about a 3% - oh, let's call it shrinkage!
Most tire calculators do NOT factor in the 3%, but this one does:
Tire Size Calculator - Tire & Wheel Plus Sizing
Why? Because they asked me about it BEFORE they designed the web page.