Sorry for the delay in articles. December and January were two very busy months of travelling, co-op hours, and school starting. This month, the two articles will be about tires and the rear sway bar. Both of these parts are vital(more so than upgraded springs and shocks in my opinion) to a superbly handling car for the street, autocross, track, etc. This article’s content will differ a bit from November’s because it is less “hands-on” than the header and more on the theory and mechanics of these two components. Note, when I mention performance in this article, it does not only mean high speed, fast, etc. driving; I mean it as in if the tire is doing its function well as opposed to mediocre or poor. Now, on to the good stuff…
Tires are one of the most important parts for your car to upgrade if you desire increased handling abilities. If you are looking up tires to purchase, you will be bombarded with a slew of numbers and letters describing the tire. The first number you should care about is the size of the tire. This number and letter combination are written on the tire wall itself. The stock tire size for the Sport Mazda 3’s with the 17” wheels is 205-50R17. So what does “205-50R17” mean? This “code” is broken down into three parts. The first part is the tire width, the “205” part labeled in green below. This is the width of the tread in millimeters. The next part, “50” is the sidewall profile labeled in orange. This is a percentage of the how much of the tread width size is in the sidewall height. If the number reads "75", then the sidewall height is 75% of the tire tread width. The last digit, “R17”, describes the wheel diameter which in this case is 17 inches, labeled in blue.
The remaining numbers won’t always be on the sidewall but they are used to pick the correct tire. There is a weight rating(noted as a number, usually in the high 80’s-upper 90’s and labeled in white above), a speed rating(noted as a letter, the closer to Z the faster it can go, also labeled in white above), and a tread wear rating(ranges from the 30’s or so all the way up to 600 and maybe higher). The weight rating of the tire determines how much weight the tire can hold before failing. Most tires for our car can hold between 1000lbs-1500lbs PER TIRE! A higher weight rating means a stronger sidewall and may also change other characteristics of the tire. The speed rating goes very high in speed for tires, some past 200 mph. Tread wear rating is how fast the tire lasts; A higher number, the longer it will last. Most race tires have a tread wear of less than 100 because a low tread wear indicates a stickier rubber which increases grip but it also deteriorates faster.
The combination of all of these numbers can be combined to pick a tire designed for your needs though not all combinations are possible between the six codes I listed.
There are three types of them: Summer, Winter, and All-seasons. Each type of tire is designed for the season in their name. The term “all-season” implies driving performance in all seasons, but this just isn’t 100% true which I will describe later. Let’s break up each category and discuss them in more detail.
Summer tires are best known for their grip and raw performance. This is THE type of tire to have for the best handling possible because the tire compound tends to be stickier and adheres to the ground more-so than other tires. As their name denotes, they are made for warmer temperatures. The rubber compound used heats up faster and becomes stickier and stays sticky. If you’ve ever heard of the term “keep the heat in the tires” or “warm up the tires”, this is just describing the process of warming the tires up so they are at their optimal temperature for providing the best grip. Summer tires also have some of the best wet condition performance. The tire treads on summer tires expel the water out from under the tire through the channels in the tread. A lot, but not all, of the tread patterns you see resemble a “V” which is one of the more efficient channel patterns to use to expel the water. From my personal experience, having a set of wheels with summer tires is the biggest "handling" upgrade you can do. Having the extra grip and feedback from a well-constructed summer tire trumps all of the other suspension mods in my book. Quick story: During my first co-op term in Charleston, I started auto-x. There was a guy at several of the events who had a first gen 3 running in the stock class only using R-comps(allowed). At the end of the day they had a PAX shoot-off where the top 10 PAX time drivers competed for $50. The Mazda guy won 2nd place compared to some of the cars that had full suspension mods and only street tires. Having the right set of tires can literally take seconds off of lap times compared to a similar or even identical car with different tires. I personally own a set of summer wheels and tires just for the warmer times of the year because of the huge increase in grip from them. I also use them for auto-x when I do go to one. A few examples of a summer tire are below.
Typical "V" shaped tread pattern common on summer tires
Dunlop Direzza Star Spec's Winter Tires
Winter tires are designed for performance in the cold weather and in snow/ice conditions. The sidewalls tend to be much stiffer so the tire stays as round as possible, compared to another tire type(Ever driven a car with summer tires below 50 degrees after it’s been sitting a while? The tire creates “flat spots” which you can feel until the tire warms up and becomes more malleable.) Winter tires have a tread pattern that is designed tol sink/push through/crush the snow or ice to gain more grip. You can even buy studded tires which are especially helpful in the ice because it is very effective in penetrating down so the tread gets grip. Winter tires are awesome in the conditions they are designed for. They help keep you safe as well as helping you get going where you need to.
Ah, the infamous All-Season tire. The stock tires on our cars(minus the Speed3’s) have all-seasons and I’m sure most people do not like them one bit. All-seasons are designed to work in all conditions, but lets be real, they are mediocre in all categories since they have to be design for all conditions. Ever heard the phrase “Jack of all trades, master of none”? Same thing applies to all-seasons. They can get the job done, but are most definitely not the best solution for it. So if an all-season tire must perform in the winter and summer, then it needs a hard rubber material and gnarly tread for the snow/ice and it also needs to be soft and have an aggressive tread pattern for the warm and dry/wet conditions. As a result, compromised is agreed upon and you get a subpar tire in each category than a tire designed for a specific season. I do understand the appeal for them and even I own a set, because they do get by and if you live in a milder climate where you may occasionally get snow and decently cold temps and warm summers and aren’t concerned with performance for the car, then by all means get an all-season but search long and hard for the right one for your needs. I personally own a set of Continental DWS’s on my stock wheels in stock size and I love them for their versatility. I’ve driven on them on the highway at speed in snow flurries and done some spirited driving with them in the spring/summer. They perform well for what they are but obviously there are better tires then them for those specific conditions. I’d recommend them to anyone who lives in VA and other similar climates if you can only afford one set of wheels and tires. If anyone else has a set of all-seasons they would recommend, feel free to post them up here.
Tire types and the performance of them cover a broad spectrum. There is a tire type out there for everyone’s needs if they know what they want and know what to look for in a tire. If you are looking for high performance from your tires then I would suggest getting a separate set of wheels for warm and cold conditions(A summer set and a winter set). All-seasons, depending on your climate and budget, can be a suitable replacement to two sets of wheels and tires but not always. If a tire has good reviews and is very popular, such as the DWS’s from Continental or the Ventus V12’s from Hankook, that is usually a good indicator of a tire performing its job well. Not all tires are created equal. My last bit of advice is this. You tires are the only components that contact the road so don’t skimp on getting the right tires or tire sets for your car, you may regret it later.
*Tire Rack has a great section on tires and everything about them if you are still curious, want to learn more, or want to fact check my article(I wrote this based off of what I know, not looking). Link is here for more detailed tire info