You probably remember the Mercedes-Benz S-Class of the W140 generation, which is strongly associated with the era of the “dashing 90s”. In the top version of the S600, it was equipped with a 6.0-liter V12 of the M120 series, but in the history of this model there could be an even more powerful engine - an 8.0-liter W18! This information was published by the German edition of Autobild.
According to the resource, even before the release of the W140 in 1991, Daimler-Benz was developing a modification of the 800 SEL - the W18 engine was being prepared for it. The engine, which was assigned the index M216, was supposed to be three in-line "sixes" combined in a single block with a camber of 75.5 degrees. Thanks to such an exotic layout, it would have turned out to be no longer than ordinary in-line "sixes".
The developers have provided two options for the engine: the base one with two valves per cylinder with a return in the region of 490 hp. and 750 Nm and forced with five (!) Valves, producing at least 680 hp. and 800 Nm. Even today, nearly 30 years later, these numbers are awe-inspiring.
There was nothing like this from other automakers in those days. Only in the late 90s, Bugatti introduced the EB118 and EB 218 prototypes, equipped with a W18 engine, but their production was never launched. Moreover, due to a number of technical difficulties, Bugatti eventually abandoned the W18 and instead developed the 8.0-liter W16, which is still used in the Chiron model.
According to Autobild, the W18 was fully developed but never made it past the blueprint stage - it was canceled before the prototype stage. Why? The answer is simple: Daimler-Benz decided that the 6.0-liter V12 met all the power and performance requirements of the wealthiest customers, and the W18 would already be redundant.
Mercedes was developing an 8.0-liter W18 for the W140, but changed its mind in the end
