Hello everyone, I drive a 2011 Mazda 3 four-door hatchback 2.5 l and I believe it's the S edition but I bought this car a few years ago from a guy and I just stumbled across something today that has baffled me a little bit. The tires that were on the car when I bought it from him were 215 55 R17 and that's what I've bought for a few years now because I've replaced every tire at least once but today when I was going through a few websites to see if that tire is actually listed sellable for my car, I noticed that tire is not listed for my car anywhere so I want to know is that a good tire for my car or should I change it because I see there's like a 215 45 R17 or maybe it was a 50 R17 listed. The tires have been running down pretty low and fairly quickly (which I do a lot of stop-and-go driving) so I didn't know if that had something to do with it being the wrong tire. Can someone advise?

 

Here's a tire size calculator. You can enter the two different tire sizes you want to compare, then it'll show you the side-by-side specs in terms of sidewall height, diameter, rotational speed, and how "off" it is from the factory-sized tire.

https://www.miata.net/garage/tirecalc.html

Plugging in the values for three different sizes:

• 215/50-17 factory -- 4.2" sidewall, 25.5" diam, 792 rpm, 0.0%
• 215/55-17 plus-size -- 4.7" sidewall, 26.3" diam, 767 rpm, 3.3% large (sluggish accel, compared to factory; speedometer issues)
• 215/45-17 minus-size -- 3.8" sidewall, 24.6" diam, 819 rpm, -3.3% small (rougher ride but zippier accel, compared to factory, due to shorter sidewall; speedometer issues)

Had a Mazda 3 S, myself. Used the standard 215/50-17 tires for it. Lots of choices, in that size. I'd recommend sticking with the 215/50-17, if you have a choice.

In the 17" rim fitment, you might go with a 225/45-17, but the rim width really is a bit narrow to be properly supporting a 225 width tire (without a less-firm handling change to the car). But I, personally, wouldn't opt for either of the fits that ends up more than 3% off the factory specs, in terms of RPM's.

As for wear, I would think the specific tire and its compound would be the greater driver of wear rates, along with your driving style, rather than the size being one larger fitment than factory. (Had a Miata for years and used many different sizes of tires on a handful of different-width rims. A sightly smaller fitment can result in noticeably-zippier acceleration but it can come at the price of a bit harsher ride quality. If you are considering staying with a non-factory fitment, consider all of the impacts. Won't necessarily be bad, but it'll be different.)