Best tire ratio

Welcome to PriusChat! Take care what you ask for! This link might help you http://www.tirerack.com/tires/tiretech/techpage.jsp?gclid=CI68vv6MstACFQ5YDQodaCoOWA&techid=46&s_kwcid=AL!3756!3!72454646413!b!!s!!+tire%20+sizes%20+explained&ef_id=UjW6WgAAAOsBPT1d:20161118103141:s



Scroll down to Sidewall Aspect Ratio.

hope this helps - Wil

PS: My 2009 Gen II was shod with Michelin Energy Savers until the beginning of this summer. I'd put on a set of winter wheels (regular 15" steel rims shod with Blizzak WS80s for the winter) but at the beginning of last summer, the car needed new tyres (state inspection), and my local Town Fair Tire guy recommended Antares Ingens A1 (no, I'd not heard of them either) as being a great summer tyre, very quiet, efficient, and about ½ the price of a set of Michelins. Michelins are great tyres, but their tread tends to outlast their sidewalls. The sidewalls on my Michelins were developing fine cracks, and the tyres were starting to get very noisy! I found the Antares to be everything I'd hoped them to be, great in the wet, whisper quiet, and perhaps not quite as efficient as the Michelins, but with gas @ $2.20/gal who cares?

 

Your OEM tires had a diameter of 25 inches and rotated 833 times per mile. If you want the speedometer to be accurate, you want the same specs for the silly 16 inch size. 205/55R16 matches pretty close 24.9 inches and 836 revs per mile. Other sizes will have more speedo error.

Since you won't have to be doing math to know if you are legal, these should be cheaper in the long run than sizes where the speedo lies.

Or you COULD wisely go back to stock.

 

Both Comfort and Economy will improve, the stock tire height is 65% if its width, there is more tire between you and the road. (if the wheel is one inch larger, the tire has to be 1 inch smaller) Since tire is lighter than wheel, a smaller wheel will also weigh less. Rotating mass is particularly bad for fuel mileage.

 

Just editorial Jimbo, should "speedometer" read "odometer"? The latter is what counts, and I fully agree sticking with stock OD is the way to go.

 

I like not to get tickets, so I worry more about the speedometer.