how do you read tire size

[prototype80]

ok how do you read tire size, i need to figure this out so i can pick which wheels i am going to order. my choices for a 17x7 wheel are

205/40/17

215/45/17

235/45/17

obviously the 17 at the end represents the size of the rim but what do the other numbers represent. i am looking for a z rated like the kuhmo ecsta supra but i know they wear out overnight from experience. www.wheelmax.com has a pretty good selection of wheels and tires take a look at the tires and see which ones you think are best. im thinking nitto

[GScivic7]

205 is width of tires
40 is ratio of width to sidewall height

I'm guessing you have a civic, you want 205/40/17 tires. 215s may be too wide and you might have problems with it rubbing. And 235s on a civic are unheard of unless you have rims in some crazy offset with wheel spacers and fender flares to cover them up.

[prototype80]

thanks i appreciate your help. i saw an article in an earlier this year super street and it had how to read a tire size and all that but my wife got a hold on my magazines now im empty handed.

[BullShifter]

You can learn all about tire sizes and what the proper size would be at www.tirerack.com or www.whalentire.com

I personally would choose a 205/45 because a thin sidewall means a poor ride. Tire sidewall are the first thing to absord bumps.

[eckoman_pdx]

205/40/R17
As was stated, the first number represents the width of the tread, in MM. So 205 means the tire has a 205M tread patch. The second number, 40, is the aspect ratio of the sidewall. It is represented in what percentage of the thread patch the sidewall is. So a 40-series tire has a sidewall that is as high as 40% of the width of tread patch. R stands for it being a "radial tire." 17 is the wheel diameter size.

If the tire is Z-rates (meaning it is rated to hold up @ speeds in excuses of 148MPH), it generally appeares in the following location: between the aspect ratio and the R--->205/40/ZR/17.

You have a Civic Hatch if I remember, so you'd probably want a 205/40/17 tire with your 17" x 7" wheels.