Short version: Give enough lift with magnetic strips under the road to reduce car weight.<p>Long version:
Here is the most practical way to get the best mileage out of existing gas car. Everyone knows most of the fuel spend in today's car is for dragging the metal around. What if we use magnets (strips under the road and bottom of the car) to give enough lift so the car can go longer distance for the same amount of fuel. I am not talking about lifting off the ground, but just enough to reduce the burden on the wheels and the car is driven the usual way.<p>Will it work ?
Bearings are already quite good. You could get the same result by using magnetic, no contact wheel bearings at a very large increase in cost, but the fuel economy improvement would be tiny.<p>The big problem is not rolling resistance, its wind resistance. Wind resistance goes up by the square of the velocity increase....double the speed and you quadruple wind resistance. The second biggest fuel consumer is the mass itself (not the weight). Accelerating and decelerating mass requires energy. Magnets might make less "weight" but they would make more mass.