Marta,
The W rated tires are not as high a rating as
a Z rated tire. Z rated tires are good for
up to 300 km/hr while the V rated tires are
good for up to 249 km/hr. W rated tires fall
somewhere in between 249-300 km/hr. H rated
tires are good for up to 210 km/hr. Hope
this helps clarify this common misconception.

1991 Laser RS turbo
1993 Talon TSi AWD
http://www.infowars.com