General Motors Buick Master Six

The Buick Master Six (also Series 40 and Series 50 depending on wheelbase) was an automobile built by Buick from 1925 to 1928. Previously, the company manufactured the Buick Six that used the overhead valve six-cylinder 242 cu in (4.0 L) engine in their high-end cars, and the four-cylinder Buick Four for its smaller, less-expensive model. After 1924, it dropped the four-cylinder engine and designed a small six, the Buick Standard Six, to replace the Buick Four. The name "Master Six" was introduced for high-end cars sharing the GM B platform with the Oldsmobile Model 30, and were powered by the 255 cu in (4.2 L) Buick inline-6 engine released the year before. The yearly changes were a result of a new business philosophy called planned obsolescence.

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