Speed rating. Wow, that sounds cool! But what is it and why is it important to me?
I still use the term speed rating from time to time. More often now, I refer to it as performance rating. In the real world, most people will not drive as fast as the tire is capable of going. The reason I call it performance rating is simple. By upgrading to a
higher speed rated tire, I can improve the handling characteristics of
my car without an expensive upgrade. It doesn't mean the car will travel
that fast, just that it will be more responsive. There will be less flex in the sidewall when cornering. I upgraded from
'S' rated (up to 112mph) to 'H' rated (up to 130mph)That has suited me just fine
BF Goodrich has a
chart that lists most of the different ratings here- (http://www.bfgoodrichtires.com/tires-101/tire-basics/about-tires/tire-speed-ratings-and-tread-life.page
I work on an island. It is rare to get my car over 50 mph, let alone 186mph. Heck, my car isn't even capable of going safely at the maximum rated speed for snow tires. (around 99mph)
So, why do they have different ratings and why does it matter to me? The handling characteristics, the sidewall strength, the extra support built in to the bead(where the tire mounts on the wheel.) the additional strength in the center of the tire and the design of the tread. Most higher performance grade tires do not have a mileage warranty and will tend to wear out quicker than one with a lower rating. Most also use a different rubber compound to help with traction.
There are other structural things in the tire that increase its strength and durability. Still, 75mph is plenty for my little car.
There may be an upgrade available on your car. Contact me and I can help look for what is available. I will give you some advice or recommendations based on your specific needs. Feel free to contact me via email- firstname.lastname@example.org