How do Performance Tires work?
The subject of this week’s How’s This Work was stumbled upon as we were doing one of our comparison landing pages recently. We were looking at the Toyota 86 and noticed it was equipped with W-speed tires while its competitor was equipped with H-speed tires, and we thought it might be a good topic to broach in order to shed light on what all of the different speeds are and what they mean.
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How to understand a Tire Type
If you’ve ever looked at what type of tires a new vehicle is equipped with, you’ve probably thought it was a bunch of gibberish. For instance, the 2017 Toyota 86 is equipped with 215/45R17 W tires. That certainly seems like gibberish, but we promise it’s not. So before we dive into speed ratings, let’s first dissect that seemingly random string of letters and numbers on your tires’ sidewall.
The 215 represents the width of the tire, in this case 215 millimetres. The 45 after the slash is then the tire’s aspect ratio, in this case meaning that the height of the tire is equal to 45% of the tire’s width. The first letter, in this example R, depict the tire’s construction type. R means that the tire’s layers run radially across the tire. Then 17 represents the diameter of the tire, in other words it tells you what size wheels it will fit on. And finally, the last letter – W for the Toyota 86 – represents the speed rating.
In some instances, more numbers might be present, like tires meant for big trucks or other such driving types. But for performance tires, this is generally all you will see. So now that we understand that, what are the different speed ratings?
What are tire speed ratings?
Hopefully this helps you out the next time you’re looking at a new performance car, or looking to buy a new set of performance tires, so that you can understand what they mean and how fast you can go on them.