http://www.uncletaz.com/library/scimath/tesla/teslacar.html
"in 1931, under the financing of Pierce-Arrow and George Westinghouse, a 1931 Pierce-Arrow was selected to be tested at the factory grounds in Buffalo, N.Y. The standard internal combustion engine was removed and an 80-H.P. 1800 r.p.m electric motor installed to the clutch and transmission. The A.C. motor measured 40 inches long and 30 inches in diameter and the power leads were left standing in the air - no external power source!
At the appointed time, Nikola Tesla arrived from New York City and inspected the Pierce-Arrow automobile. He then went to a local radio store and purchased a handful of tubes (12), wires and assorted resistors. A box measuring 24 inches long, 12 inches wide and 6 inches high was assembled housing the circuit. The box was placed on the front seat and had its wires connected to the air-cooled, brushless motor. Two rods 1/4" in diameter stuck out of the box about 3" in length.
Mr. Tesla got into the driver's seat, pushed the two rods in and
stated, "We now have power". He put the car into gear and it moved forward! This vehicle, powered by an A.C. motor, was driven to speeds of 90 m.p.h. and performed better than any internal combustion engine of its day! One week was spent testing the vehicle. Several newspapers in Buffalo reported this test. When asked where the power came from, Tesla replied, "From the ethers all around us". Several people suggested that Tesla was mad and somehow in league with sinister forces of the universe. He became incensed, removed his mysterious box from the vehicle and returned to his laboratory in New York City. His secret died with him!
It is speculated that Nikola Tesla was able to somehow harness the earth's magnetic field that encompasses our planet. And, he somehow was able to draw tremendous amounts of power by cutting these lines of force or causing them to be multiplied together. The exact nature of his device remains a mystery but it did actually function by powering the 80 h.p. A.C. motor in the Pierce-Arrow at speeds up to 90 m.p.h. and no recharging was ever necessary!"