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The 8.5% RPM drop - from 2500 RPM to 2200 RPM from the smallest to largest circumferenct tires you list - will likely save fuel.
I switched final drives in my car, and dropped my RPM by 25% for a given road speed, and saw roughly a 6% improvement in fuel economy on the highway.
The potential trouble with doing a tire swap is you're also raising the car's ride height, which will probably increase aero drag. Maybe not a lot, but look at "eco" versions of European car models, and many have a lower ride height than the regular versions, on the order of about 15-20 mm.
As well, going from 185 to 195 width also increases drag by increasing Cd & frontal area (yes, slightly).
And lastly: would the rolling resistance of the tire you switch to be better or worse than the tire that's on there now? That's something to consider too.
So you're potentially changing a lot of variables, some of which oppose each other in terms of efficiency. If I were going to do this, I'd want to be able to empirically test it before spending the money. (Borrow someone else's rims with taller tires? And even then, are the rims aerodynamically the same as yours?)
And don't forget you'll also need to either recalibrate your speedo/odo, or manually do the calc to your distance to know if it's had an effect on MPG.
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