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Right size wheels & tires

The Right Size Wheels & Tires

This is a tough question to directly answer because it depends on your Civic’s year and how much it has been lowered. In general, these are the recommended maximum wheel sizes (in inches, height x width): This will help you find the right size wheels.Right Size Wheels

Example:

  • 4th – 6th Generation Civics (1988 – 2001): 17 x 7.5
  • 7th Generation Civics (2001-2005): 18 x 7.5
  • 8th Generation Civics (2006+): 19 x 8

Keep in mind these guidelines are for stock suspensions only. Using the maximum size may require “rolling” your fenders. You will also have to be more conservative if you’re lowered. Remember that very large wheels will also hinder your Civic’s performance because of the added weight of the wheels. Each extra pound on your wheel really does make a difference because it adds to both the rotational inertia of the wheel and the vehicle’s total “unsprung” weight. Unsprung weight consists of parts that are not held up by the suspension; increasing unsprung weight prevents your suspension from performing at its best.

Your selection of tire size also plays a role in fitment. Here is a quick overview of how tires are currently measured:

Sample Tire: 195/55ZR15 89Y
Measurement What it Means
195 The section width. This is how wide the tire’s contact patch is (in millimeters) when inflated.
55 The aspect ratio. This is the ratio between the tire’s section height and section width. Section height is just the height of the rubber you see around the wheel, multiply it by 2 to get the total vertical space that the rubber takes up.
Z The letter Z is present here only if the tire’s true speed rating is in excess of 149 mph. The old way of measuring tires actually had the tire’s speed rating here. Tire buyers got used to seeing the “ZR” on a tire as meaning “high performance” and so tire manufacturers have kept it here eventhough it is not necessary. Note that, just because a Z is present here, it does not mean that the tire’s true speed rating is a Z – it could be a W or Y, which are both ratings above 149 mph.
R The R stands for Radial, which is how the tire is constructed. Don’t worry about this because almost all tires are now radial.
15 The inside diameter of the tire. Always match this with your wheel diameter.
89Y The “Service Description”, which is a load index number combined with a speed rating. With Civics and other imports, you usually don’t have to concern yourself with the load index as it is always sufficient for how the tire is intended to be used. The higher the load index, the more weight a tire can hold. For example, a load index of 85 means each tire can hold 1135 lbs and a load index of 91 indicates 1356 lbs per tire.

The speed rating is the tire’s maximum recommended speed. Some common ratings are: H = 130 mph, V = 149 mph, W = 168 mph, Y = 186 mph, Z = 149+ mph (a Z rating technically means “above 149 mph” but in practice it usually means “somewhere above 186 mph”. It is best to consult the tire manufacturer to get the true maximum recommended speed on Z rated tires.)

Note: To convert millimeters to inches, divide by 25.4.

One easy way to upgrade your wheels/tires (if you don’t use our wheel/tire size calculator) is using the “plus sizing” system. Plus sizing is a technique to reliably upgrade your wheels/tires so that the total height of your wheel + tire remains roughly the same (within 3%). This will prevent rubbing, maintain your speedometer accuracy, and prevent brake failure. If you follow this system your total wheel + tire height will be within 3% of your stock wheel + tire height, and you will not have any problems. The plus sizing system is very simple and goes as follows:

Plus 1:
Increase wheel diameter by 1 inch
Increase tire section width by 10mm
Decrease tire aspect ratio by 10 points

Plus 2:
Increase wheel diameter by 2 inches
Increase tire section width by 20mm
Decrease tire aspect ratio by 20 points

So if you had 195/55ZR15 tires and 15″ wheels, a Plus 2 upgrade would consist of 17″ wheels with 215/35ZR17 tires. The plus sizing system, however, does not work accurately above 2 sizes. It is also not recommended to go below an aspect ratio of 35, as this will not provide enough “cushion” for your wheels. As far as tire width goes, you should choose a tire that is between 0.8 and 2.0 inches wider than your wheel. Wider tires will “bulge” more and offer more protection for your wheels, but will also increase the chance of rubbing if you’re lowered or using very large wheels.

Lastly, here are some other concepts that are important in finding the right size wheels or tire selection:

Term Definition
Hubcentric / Lugcentric These are the two ways to center wheels when you mount them. Lugcentric uses the lug nuts themselves to center the wheel, and is an older technique. Hubcentric is the newer, better technique which centers the wheel around the hub. Most aftermarket wheels make the hub hole (centerbore) oversized and come with adapter rings (hubcentric rings) to center the wheel on the hub. Hubcentric rings are either metal or high temperature plastic. If you don’t use them, your wheels may vibrate.
Offset This is how far the mounting surface of your wheel is from the “centerline” of the wheel. A more positive offset will cause your wheel to mount closer to the inside of your wheel wells. For Civics, it is a good idea to stay within the +35-45mm offset range when upgrading (thin wheels will be closer to +35mm, wide wheels will be closer to +45mm). A wrong offset can cause rubbing problems, either on the fender (offset too low) or on the inside of the wheel well (offset too high).
Bolt Pattern (PCD) Specified by the number of wheel bolts and the diameter (a.k.a. PCD or Pitch Circle Diameter) of the imaginary circle made by connecting those wheel bolts. For Civics, if you have 4 bolts then its 4 x 100mm, 5 bolts is 5 x 114.3mm. These are standard sizes for all years.
Wheel Spacers Wheel spacers can help with rubbing problems on the inside of the wheel well by pushing your wheel out more. This can also create a “wide look” that some people like. You’ll also have to get longer wheel studs to assure proper mounting of the wheel on the wheel spacer.

For installation, tighten each lug nut to about 80 lb-ft of torque, using a criss-cross pattern. For new wheels, re-tighten each lug nut after about 100 miles of driving.