YACT: Would P225/45R17 tires be interchangeable with P235/45R17 tires?

[BillGates]

I am looking for a set of winter tires for my car and found a good deal on eBay for a set that is P225/45R17. My OEM size is P235/45R17.

I'm not concerned with my speedometer's accuracy as much as I am with it being possible to put the tires onto my wheels (8.0" wide) and them working "normally." Any ideas?

 

[cjgallen]

Between those tire sizes, only the width is different (the set on ebay isn't as wide), height/aspect ratio is the same so it won't affect your speedo.

I wouldn't put skinnier tires on my wheels though, they might not fit right.

225mm = 8.85 inches so they might work

 

[Zenmervolt]

Originally posted by: cjgallen
Between those tire sizes, only the width is different (the set on ebay isn't as wide), height/aspect ratio is the same so it won't affect your speedo.

WRONG.

45% of 225mm is less than 45% of 235mm. The aspect ratio is exactly that, a RATIO of the tire's sidewall height to its width. 45 series tires have a sidewall height that is 45% of the tread width.

225/45 tires have a sidewall height of 101.25mm. 235/45 tires have a sidewall height of 105.75mm. The 225/45 tires will be shorter and will cause his speedometer to read higher than true.

So short answer: Yes the tires will fit. They will, however, throw off your speedometer and will make the miles come onto the odometer faster.

ZV

 

[Grouchyoldguy]

Here is a handy little link for those changing tire sizes.... http://www.miata.net/garage/tirecalc.html