The VI scale goes from 0 to 100 , with 0 being the worst , and 100 being the best . The temperatures chosen arbitrarily for reference are 100 a. The original scale only stretched between VI = 0 ( worst oil , naphthalene ) and VI = 100 ( best oil , paraffin ) but since the conception of the scale better oils have also been produced , leading to VIs greater than 100 ( see below ) .