Articles » Basic Mods Part 2

Thank you for your continued interest in my series of articles explaining the various modifications available and what exactly they do. This is the second in the series and in it we will discuss how to make your car handle and stop better.

We’ll start off with probably the most obvious of choices, wheels. I must make a few clarifications here on terms I will use throughout this section. Wheel means the overall combination of the tire and the rim. The tire is of course the rubber that wraps around the rim and the rim is the metal/aluminum part of the wheel. Rims can greatly improve performance and handling of your car, but they can also make or break how clean your car looks. Let’s take the standard civic EX with its 14-inch diameter by 4-inch width rim (I believe…although they maybe 5 inches wide). Now, let’s say you pick out some really nice aluminum alloy rims for it, say Racing Hart CP-035 rims (pictured above) in a 17x7 inch size. Obviously your stock tires will not fit, so you’re going to have to get new ones. The best size in my opinion would be 205x40x17, although 215x40x17 would fit too. Those numbers represent the measurements of a tire and are located on the side of every tire made. The 205 is the tread width in millimeters, the 40 is the aspect ratio, or the size of the sidewall as a percentage of the tread width. So the sidewall in this case is 40% of 205. The final number is the radius of the rim that the tire will go on.

Okay, back to the subject. This rim is of an aluminum alloy construction weighing in at only 7 pounds, much lighter than stock. This means that your car will be able to accelerate much faster because of the decrease in the amount of power it takes to rotate the wheel. The next benefit is the handling. Since the wheel now has a lower profile tire (the 40 part), it is a lot more responsive to turns because there is less tire to flex and give when you put lateral (sideways) force on it. This is why you see Porsches and Ferraris with really thin looking tires: better handling. A third benefit is the type of tires you choose to use. More than likely they are going to be Z-rated or higher. Every tire has a letter rating indicating the maximum speed at which it’s still safe to use that tire. Z-rated tires are rated for about 148 mph. They are also softer than your average tires, which will increase traction for improved handling and braking response, but will also cause them to wear out faster than your stock tires. Most, if not all Z-rated tires don’t have a mileage warranty because they are so soft and have the potential to wear out quickly. I’ve had mine for almost a year now and they’ve only lost about ¼ of their tread.

Now, as you probably have guessed, there are negative effects from this. The rims I used as an example are very very light rims, but in most cases, your average 17-inch rim will weigh in around 17-20 lbs. This is considerably heavier than stock and the concentration of the weight is farther out, requiring even more power to rotate it. These will slow down your car noticeably, but not hugely. A general rule is that the bigger the rim, the heavier and more it will slow down you car. However, the appearance of your car with the new rims maybe enough to offset this effect. You’ll also have to be more careful with potholes. Since you have a lower profile tire (thinner), you have less rubber and air to cushion the rim before it makes contact with the ground causing it to bend.