As far as the 32 ft lbs of torque, i was just estimating a quick calculation of 8 lbs times about 4 ft high and that's 32 ft lbs of torque. Now...that's not really the whole story. The force of the 8 lbs is directed down unless the car was flipped on its side. What you really want to look at is, the mass difference in the roof times the lateral acceleration of the car and the height of the mass you are changing if you want the real torque the roof provides on the car.