1981 Mercedes-Benz 380 SEC and 500 SEC The 380 SEC and 500 SEC made their debut at the Frankfurt International Motor Show in September. The luxury coupés were based on the W 126 S-Class and replaced the SLC but were clearly more imposing. The V8 engines, which had been revised for model year 1981, developed 204 hp (380 SEC) and 231 hp (500 SEC).	1976 1977 1978 1979 1980 1981 1982 1983