I know the W is rated up to 168 mph, but what does the Z mean with the 148+? what's the + go up to? is Z better than W? thanks.

 

Back a long time ago they never figured that anything faster than 149mph would be neccessary or even really possible on a regular road car, so they just said 149+

well then they started to realize a lot of cars can go much faster than that so they introduced a couple of new speed ratings.

 

V - 149 mph
Z - 149mph +
W - 168 mph (better)
Y - 186 mph (best as of now)

 

cool, thanks. so what does Z go up to? and is Z better than W?

 

[QUOTE]Originally posted by LordMagnet
[B]cool, thanks.

 

[QUOTE]Originally posted by koala
[B]

W is better... Z is just a generic rating...

 

What does it matter really? I mean, how fast are you going to go 149+? The S2000 can barely go much higher than 155 anyway.

 

Me and my friends are just curious, no one seems to know. I'm perfectly happy with my W rated tires.

 

A wierd observation.

When a tire company makes the same tire, same size, but just different speed ratings, frequently the "W" version is cheaper than the "Z" version.

Maybe the more expensive the better does not apply in this case.

My take is I'll probablly never notice the difference, so I'll go with the cheaper one. If it's the "W" that's cheaper, then I guess I make out if they are better.

 

Koala is correct. They had to add Y and W because there are stock cars that exceed 150 mph. Some of the Z speed rated tires may have been able to be Y or W but the test was ended once they achieved the Z. At that time the speed rating was 150+. Now they put a limit on the tires to cover their butts. It really isn't that one is better than the next.

Jim