High Quality Content by WIKIPEDIA articles! The BMW M30 is an inline-6 cylinder engine built by BMW and was used in many different models since 1968. It was originally developed in the late 1960s as an extended 2.5 liter version of the robust inline four cylinder BMW M10 first used in the 'Neue Klasse' BMW 1500, with which it shares a number of design features, including a 30-degree cant to the right for a lower profile, a crossflow head design, and a chain-driven single overhead cam with rocker arm valve actuation. The 'Big Six,' also known as the 'Senior Six,' got its informal names after the introduction of a smaller BMW M20 belt-driven SOHC six cylinder in the late '70s. The M30 powered a series of BMW 6-cylinder E9 and BMW E24 coupes to European Touring Car Championship (ETCC) throughout the '70s and into the middle 1980s, even though a more powerful DOHC 24-valve head had been developed for high performance motorsports and street use.