What do the numbers in the size of a car tire indicate?
dragon asked:
I am looking to get new tires on my car today and have P185/70R14 on my car right now. Do I have to buy tires with this exact size for the rims I have on my car? Or, is there some play with some of the numbers? I know the 14 indicates 14inch rims but don’t understand the rest of it.
http://www.teambuildingdirectory.com/blog/
This entry was posted
on Monday, August 10th, 2009 at 12:41 pm and is filed under Maintenance & Repairs.
You can follow any responses to this entry through the RSS 2.0 feed.
You can leave a response, or trackback from your own site.
I am looking to get new tires on my car today and have P185/70R14 on my car right now. Do I have to buy tires with this exact size for the rims I have on my car? Or, is there some play with some of the numbers? I know the 14 indicates 14inch rims but don’t understand the rest of it.
http://www.teambuildingdirectory.com/blog/
August 10th, 2009 at 2:51 pm
The P means it is metric.
The 185 is the width
The 70 is the aspect ratio, (the height of the sidewall)
R means it is a radial tire.
August 11th, 2009 at 8:58 am
the first number refers to the width of the tire, the second the height of the sidewall, and the last is the diameter of the wheel itself, you have to stay with the 14inch wheel’s unless you want to buy new one’s, but there is a little leeway in the size, talk to your tire dealer and see what they can do for you
August 13th, 2009 at 10:12 am
The 185 means the width of the tire in Milimeters.
The 70 means 70% of the width. The lower this number is the lower the profile of the tire. On a 14 inch tire there isn’t much room to play with.
August 16th, 2009 at 10:40 pm
There are three numbers:
1.) Width of the tread in millimeters, 185mm is roughly 8.4 inches, you sometimes go up 10mm to 195mm.
2.) Ratio of sidewall to rim, going higher or lower, will throw your spedometer out, because the overall circumfirance of the wheel will be larger. Again, not recommended.
3.) The last is the rim size - not at all optional.
Your best shot at monkeying around with these numbers is more than less getting new rims & tires.
August 20th, 2009 at 5:09 am
185 is the approximate width of the tire in mm(basically) and the 70 means that the sidewall height is 70% of the tire width.
P means it’s a metric-measured tire and R means it’s a radial.
If you buy something with a substantially different circumference you will have to have your speedometer gearing (or programming)changed.
August 21st, 2009 at 10:24 am
The recommended size for your vehicle from the manufacture is designed for the best riding, fuel mileage and wear, if you change the tire to a bigger size, you must change the alignment also. Also by going to a different size, the tires may hit the steering linkage when turning. You could try a little bigger size, maybe a 195/70 R14, yes 14 is rim size, 185 is raduis, I believe the width 70, 60 is a low profile tire, 50 lower profile, 80 is a slimmer tire. Stick with what the manufacture recommends, just my opinion.
August 23rd, 2009 at 5:04 pm
Everyone told you what the numbers mean.
Now for the rest. You can put slightly WIDER tires on, and you can put tires on with a lower or higher aspect ratio, but the 14 isn’t changable because it is the size of the rims.
Narrower tires are better in snow and mud, believe it or NOT.
Remember that if you put WIDER tires on, your gas mileage will go down.
If you put HIGHER ASPECT tires on, the actual outside diameter of the tire is bigger, so theoretically your gas mileage will go UP, however most cars do not have enough room in the wheel -wells to allow taller tires installed.
Taller tires will also throw your speedometer off. You will be driving faster than your speedometer indicates.
August 24th, 2009 at 4:45 am
P185/70R14 In that 185 Indicates Tread Width, 70 Indicates Aspect Ratio and 14 Indicates Rim Width.