Naive question - tire size

Thanks Edward for the quick reply. Yes, my snow tires come with rims. So they should work with her car?

Right. If her information is correct, her rims are an inch bigger than yours.

I'm not knowledgeable enough to tell from the numbers you gave, but if you trade tires and rims (I assume the lug patterns are the same so you can), both your speedometers might then be off.

Don't worry about the fact it says "Miata", it's not just for Mazda Miatas.

Tire size calculator

You'll see when you plug in the two tire sizes, that there is only a

0.5% speedometer error between the two tire sizes. In other words, it's a near perfect match.

In general, you will find that when a manufacturer gives many different tire size options, all of those options have been chosen by the mfg to have the same circumference, more or less.

Yousuf Khan

On Fri, 29 Apr 2005 02:12:48 GMT, "Jack" wrote in news: snipped-for-privacy@comcast.com:

Given that your tires are already on 15" rims and those rims clear the brakes, they will be a good match with less than a 1% theoretical difference in circumference.

Many vehicle with larger wheel sizes use the extra room to fit larger brakes. I have had a couple of vehicles where only the OEM wheel would clear the brakes without going up an inch in diameter for non-OEM wheels due to the design. Steel wheels were not an option.

As long as the lug patterns the same, those wheels & tires will be fine on her vehicle.

I've had it worse. I bought steel rims (for winter) for my Nissan NX2000 from a wrecker. Unfortunately they only had

3, and I had to order one from Nissan directly. They were all the same size. Except when I put them on the second year (and was rotating them) I noticed that the one from Nissan directly didn't clear the front brakes. All of the other 3 were fine.

It turns out that the NA built NX2000s had a different (larger) set of front brakes on them than the Japanese built ones. Both were imported for the same years.

Moral of the story? Try them on the car and check clearances before you close the transaction.

Er, make that (smaller). The JAPANESE model's had larger front brakes.

I need caffeine.