Ford Motor Company has purchased two Cray SV1 supercomputers, bringing the company's total to five, Cray said today. Ford will use the machines to conduct safety tests and structural analysis. The new machines replace earlier Cray J90 computers. By running simulations of noise, vibration and harshness, the computers can be used to speed development of automobile prototypes. The SV1's successor, the SV2, is due in 2002.