What are all the tire ratings, what do they stand for, and how much speed will they take, like I know they have several different tires, with ratings like Z, S, R, etc, but I have no idea what their ratings are.

 

from tirerack.com

rating max speed
M 81 mph
N 87 mph
P 93 mph
Q 99 mph
R 106 mph
S 112 mph
T 118 mph
U 124 mph
H 130 mph
V 149 mph
W 168 mph
Y 186 mph
Z isnt defined because tires ability to endure high speeds keeps increasing...so z pretty much means yes...it will go that fast

 

thats funny, but what about zr thats what my falken ze-512's are rated at. nvm i'ma idiot. there rated at w which is 168 mph which is faster than i'll be going . but what does the zr stand for anyway?

 

ZR doesn't stand for anything by itself.

The Z stands for "any speed over 149 mph"

and the R stands for radial

 

See, it's great to have a tire pro here. Thank you for that Colin. [sm=smiley20.gif]

 

No kidding, because that's something I've always wondered about.

 

oh, ok thanks alot.

 

All,
I have a 73 mustang convt. with 14inch tires and rims, I am looking to possibly upgrade to larger tires and rims and in specific I like the Magnum 500's. Any thoughts on this? Basically will I have to modify anything with regards to the Drums (rear) or Disc (front) breaks? Thanks John

 

You can upgrade without issue as long as the wheels are right for your car. With a proper fitment, you should not have to modify your brakes.