Plus sizing is the practice of replacing an automotive wheel with one of a larger diameter fitted with a new tire of lower aspect ratio so that the new tire has the same diameter and circumference as the original tire to prevent any changes in speedometer accuracy, torque and traction control, while reducing sidewall flex and (generally) increasing cornerning ability. The number following the "plus" describes the number of inches which is added to the diameter of the rim. For example, plus one sizing means increasing the wheel by one inch – from a 15 inch to a 16 inch, for example. A "plus zero" upgrade means changing to a wider tire size while using the same diameter wheel. Changing to a wider tire requires reducing the aspect ratio (the second number in the sequence of numbers that describes the tire's size). Since the aspect ratio is a percentage which is used to calculate the height of the tire's sidewall, if follows that if a larger number is used for the width, a smaller number must be substituted if the final result is to remain the same—which is the objective of Plus sizing.

These are simply examples and do not represent all of the possible combinations which could achieve the same result. For an R16 tire, 205/60, 225/55, 245/50 and 275/45 width/aspect ratio tires have essentially the same diameter. The exact dimensions of tires in the same size might differ slightly depending on tire brand, model, etc. Some people claim larger wheels wear faster. Wheels with reduced sidewall heights may increase risk of damaged rims, breaking the bead, and/or damaged sidewalls. The increased width of the contact patch of wider tires may increase the risk of hydroplaning. Plus sizing tires may enhance the vehicle's value. Improving the vehicle from the factory specifications may increase value. The additional height and weight of plus sized wheels may reduce vulnerability to rollovers, particularly by changing the center of gravity. During rapid tire deflation at speed, reduced sidewall height may decrease rollovers. Total wheel weight (tire & rim) is part of the unsprung weight of the vehicle and will have a great effect on traction while traveling over uneven terrain as the wheel can respond quicker (lighter weight) to terrain changes.

This allows the wheel to get back on the ground more quickly.Hvac Roof Curb Cad DetailsReading Your TiresWhen it's time to replace your tires, you have to know what brand and type you want, as well as their size. Teacup Puppies For Sale GumtreeThis information is printed on the sidewall. Toy Cockapoo Puppies For Sale In ArkansasBrand name and tire name are easy enough to find -- sometimes they're even printed in raised white letters. Tire size is measured in a combination of millimeters, letter codes and inches. The size of the tire pictured above is: P205/60SR15. The first letter is "P" for passenger tire. The first number is the tire's width in millimeters -- in this case 205mm. The second number is its aspect ratio -- the ratio of sidewall height to width (also known as "profile").

In this case the sidewall height is 60 per cent of 205mm -- or 123mm. This tire is speed-rated, so the second letter is the speed rating -- in this case it's "S" (112 mph). Speed ratings give a general idea of a tire's overall performance characteristics -- a family sedan needs no more than an "S" rated tire, while a Ferrari will use a "Z" rated tire. Tires with high speed ratings are more expensive and shorter-lived than tires with low speed ratings. Speed ratings use the following letter codes: The next letter is "R" for radial construction -- a superior design to the bias ply tires of old. The last number designates the wheel diameter -- this tire mounts on a 15-inch wheel. Sometimes a load index and a speed rating are printed together following the size designation. This tire's size is: P205/60R15 85S. "85S" means that this tire's load index is 1135 lbs. and it has a speed rating of "S." This means that four tires can safely carry a maximum weight of 4540 lbs. (4 tires x 1135 lbs.) at 112 mph.

This is something most drivers never have to worry about, but here's a sampling of some load ratings: Some light truck tires use a different sizing system. This tire's size is LT 31X10.5R15. The first two letters stand for "light truck." The first number is the tire's diameter in inches -- in this case, 31-inches. The second number is its width in inches, 10.5-inches. The "R" stands for radial. The 15 designates wheel diameter -- this tire is made to fit on a 15-inch wheel. The very small type on the tire's sidewall contains the following information: Uniform Tire Quality Grades are also printed on the sidewall. These grades are a result of government mandated tests that measure treadwear, traction and temperature resistance. The actual testing and grading is done by the manufacturer, so take these ratings with a grain of salt. Treadwear measures how long the tread should last compared with a reference standard of 100. A treadwear rating of 400 means that the tread wears four times as well as the standard.

This grade is only accurate for comparing tires within a certain brand. Traction is a measurement of a tire's ability to stop in a straight line on a wet road. The highest grade is AA; and C is the worst. Temperature measures a tire's ability to withstand the heat build up caused by prolonged high speed driving, underinflation, or overloading. The highest grade is A; Means the tire has the minimum required mud and snow traction. Maximum Load: Maximum weight that the individual tire can support -- shown in pounds or kilograms. Maximum Inflation Pressure: Shown in psi (pounds per square inch) or kPA (kilopascals). Never inflate your tires over the maximum inflation pressure. D.O.T. Serial Number: Shows compliance with Department of Transportation regulations along with the coded name of the tire manufacturer and the place and date of manufacture. The date of manufacture is shown by the last three digits of the serial number -- if it ends in 405, that means the tire was made in the fortieth week of 1995.