The easiest way to distinguish models is by checking the engine. For the Spectrum which was produced from 1985-1989, only 2 engines were ever available. Most models were equipped with a 2 barrel carbureted 1.5L engine, thought a few produced in 1987 and 1988 came with a turbocharged, fuel injected version of the same engine. The Storm was produced with 3 possible engines. For all years, 1990-1993, the base model was equipped with a 1.6L SOHC fuel injected engine. For 1990 and 1991, the GSI performance model was equipped with a DOHC version of the same engine. For 1992 and 1993, a larger 1.8L DOHC engine was provided for the GSI models.