 In 1968 the 2.5L M129 of the 250SE was superseded by the 2.8L M130, the ultimate variant of the mid-sized six, obtained by increasing the bore by .The result was a bore × stroke of ; ), the maximum practical enlargement of the engine given the limitations of the block, which required deletion of water passages between the cylinders.It was used in the W108 280S and 280SE, in the W109 300SEL from December 1967 to January 1970, and in the W113 280SL.