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These numbers are too damn confusing...

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Old 06-16-2008, 09:47 PM
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Default These numbers are too damn confusing...

So like 315/??/??? are too big for 10.5 or so I've read (theres ?'s because I have absolutely no idea what those numbers are).

I guess 295's would be good for 18's in the back? What would be good for 17's up front? And can someone help me with the other numbers?

http://tomzwheels.com/catalog/produc...roducts_id/247

^^ Those are what I'm getting.
Old 06-16-2008, 09:50 PM
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http://www.discounttire.com/dtcs/infoSidewall.dos

A 10.5 is the smallest wheel I would recommend putting a 315 on. It will still buldge quite a bit. Do a 305/35 or a 295/35 for the best fitment.
Old 06-16-2008, 10:01 PM
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The first number is the width of the tire in millimeters. The second number tells you how tall the sidewall is as a percentage of the width. I will convert to inches as it is easier to explain. If the tire is 10 inches wide and the second number is 40, that means the tire would measure 4 inches from the inside ring to the outside of the tire. If the second number is 50 that measurement would be 50. The last number is the diameter of the inside ring of the tire. I hope this helps.

The most popular combo for the 17x9.5 and 18x10.5 wheels is a 275/40/17 for the front and a 295/35/18 on the rear.

Anything over the 295 width on the rear may give you clearance issues on the 18" wheel.

Tom
Old 06-16-2008, 10:08 PM
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heh...I feel your pain. I can't stand the way tires are measured these days. I remember the old days when it was easier. The way I understand it is, 315/35/17 means the tire is 315mm wide at it's widest points, the sidewall is 35% of 315mm and it fits a 17" rim. The problem with these numbers is all manufacturers tires measure differently anyway, so you can't trust what's printed on the tire. The best thing to do is find a tire size you and brand you want on TireTRack and then choose the Specs option. It will give you an idea of the true height and width for most brands. Here is TireRack's description:

Width x Aspect Ratio = Section Height
Section Height x 2 = Combined Section Height
Combined Section Height + Wheel Diameter = Tire Diameter

Example: 185/60R14 85H or 185/60HR14

185mm x .60=111mm
111mm x 2=222mm
222mm + 355.6mm(14")= 577.6mm or 22.74"

The first number is the width of the tire in millimeters, measured from sidewall to sidewall. To convert to inches, divide by 25.4 In the example above, the width is 185mm or 7.28".

The second number is the aspect ratio. This is a ratio of sidewall height to width. In the example above, the tire is 7.28" wide, multiply that by the aspect ratio to find the height of one sidewall. In this case, 185x0.60=111mm or 7.28"x0.60=4.36".

The last number is the diameter of the wheel in inches.

To figure the outside diameter of a tire, take the sidewall height and multiply by 2,(remember that the diameter is made up of 2 sidewalls, the one above the wheel, and the one below the wheel) and add the diameter of the wheel to get your answer.
Old 06-16-2008, 10:24 PM
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Originally Posted by TomZwheels
The first number is the width of the tire in millimeters. The second number tells you how tall the sidewall is as a percentage of the width. I will convert to inches as it is easier to explain. If the tire is 10 inches wide and the second number is 40, that means the tire would measure 4 inches from the inside ring to the outside of the tire. If the second number is 50 that measurement would be 50. The last number is the diameter of the inside ring of the tire. I hope this helps.

The most popular combo for the 17x9.5 and 18x10.5 wheels is a 275/40/17 for the front and a 295/35/18 on the rear.


Anything over the 295 width on the rear may give you clearance issues on the 18" wheel.

Tom
Perfect. Do you by chance have a recommendation for a set of tires from your site?

Math + Me = Bad <= Thats about the only math I can do.
Old 06-17-2008, 05:21 PM
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Bump, any recommendations for tires from Tomz?




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