The most powerful engine ever fitted to W126 S-Class was 5.5-litre V8, putting out 221 kW (300 PS, 296 bhp). This engine, classified as ECE-Variante (German name), has higher compression ratio of 10:5 and cannot be retrofitted with catalysator at later date. In September 1986, the ECE-Variante was superseded by RÜF-Variante, which retains the same horsepower figure without catalysator and lower figure if retrofitted with catalysator at later date. The 560 SEL with 221 kW engine was fastest…
The most powerful engine ever fitted to W126 S-Class was 5.5-litre V8, putting out 221 kW (300 PS, 296 bhp). This engine, classified as ECE-Variante (German name), has higher compression ratio of 10:5 and cannot be retrofitted with catalysator at later date. In September 1986, the ECE-Variante was superseded by RÜF-Variante, which retains the same horsepower figure without catalysator and lower figure if retrofitted with catalysator at later date. The 560 SEL with 221 kW engine was fastest large saloon, reaching 250 km/h (155 mph), until BMW 750i/750iL was introduced in 1987 with ungoverned top speed of 300 km/h (186 mph). Its performance was comparable to Porsche 911 Carrera 3.2 or Ferrari Mondial. In 1990, 560 SEL had a reduced horsepower figure to 200 kW (272 PS; 268 bhp).