Join Date: Oct 2014
Location: Cleveland, OH
Vehicle: 2010 SLK 350 with Sport Pkg
Other Toys: Model planes
Mentioned: 3 Post(s)
Tagged: 0 Thread(s)
Quoted: 198 Post(s)
Thanked 56 Times in 53 Posts
The real questions is what rim width is necessary for the size of tire you intend to select?
Given a known rim width, there are quite a few tires that'll fit on it, but it is a mistake to assume all brands of a tire of a particular dimension will fit. The the inflated tire needs room to spread out on the rim to perform at its full potential, and the rim might not be wide enough. On the other hand, you may find a much fatter tire will fit on your stock rim.
Obviously, most petrol heads want the fattest, measured by section width, tire on the rear while a somewhat skinnier tire on the front. BTW, don't assume the tread width increases with section width. You have to check this number out too.
Tire Rack has your answer in the tire specification table which will tell you the range of rim widths a particular tire will fit on. But there is a correct way to select your tire:
1. First you should select your brand. Again TR will provide you with tons of data comparing the performance of various tires. For me, I simplify the process as just choose the top rated brand as determined by Consumer's Reports which always is Michelin!
2. Next starting with the stock tire size, I start examining different tires by section width. Unfortunately, it starts getting complicated due to the the overall diameter of the tire changing depending upon section height. An example:
Consider a 245/35/18 tire. The first number is section width, don't confuse this with tread width, and the second is section height. To find overall height or diameter do 2(245 X .35) + 457.2 = tire diameter in millimeters.
Now you have to compare the height of the rear tire to the height of the selected front tire. If you aren't careful, the nose of your car will be pointing uphill rather than down hill! Don't laugh, it happens all the time.
After a little effort, you'll be immensely happy!