Adequate Following Intervals
The graphic above shows that someone
traveling at 65 miles per hour will take about 6.2 seconds
and 400 feet to stop (given a common perception/reaction
time of 2 seconds and hard braking).
It is important to
note that many passenger car tires are not designed to steer
out of problem areas at speeds beyond 75 mph. At these speeds,
high speed rated tires are required due to sidewall flexion
and turning movements.