At critical velocity we can observe that the centripetal force is equal to the frictional force offered by the tires of the car
ie., m*v^(2)/r = μmg
where, m = mass of the car, v = maximum velocity of the car before it slides off the circular path, μ = Coefficient of kinetic friction between the road and the tires, g = Acceleration due to gravity & r = radius of the circular path traced by the car.
v=(μ*r*g)^(0.5)
therefore v = 14 (m/s) is the max velocity any car or truck or anything massive or minuscule can achieve before slipping out of the circular path for the given coefficient of friction between the road and the tires and the radius of the circular path.
