They used to be V rated but because they are for drag racing they won't speed rate them anymore. V is 149 mph for an hour with no damage. There aren't many 149 mile long drag strips.
The temperature rating is low and as the tire heats up it gets softer and the softer it gets, the more it heats up.
I wouldn't use them on an Open Road Race car, but I wouldn't hesitate driving 100 mph for extended periods of time on them.
130 - 140... that's another story.