1929 Duesenberg Model SJ Convertible Sedan
Of the roughly 481 Model J chassis produced between 1929 and 1937 (including supercharged SJ and later SSJ variants), the Murphy-bodied convertible sedan stands among the most sought-after configurations.
The Walter M. Murphy Company of Pasadena, California accounted for approximately 125 Model J bodies in total, and the convertible sedan was among its most successful designs (four-door practicality combined with a folding top, proportioned with the clean, uncluttered lines that distinguished Murphy’s work from the more elaborate coachwork found on competing chassis).
Beneath the long hood sat Duesenberg’s 420 cubic inch twin-cam straight-eight, producing 265 horsepower at 4,200 rpm and backed by a three-speed manual gearbox. Four-wheel hydraulic brakes were standard, and extensive use of aluminum throughout (including the engine) reflected advanced engineering for the era. A stock Model J was capable of exceeding 100 mph.
The supercharged SJ variant, introduced in May 1932 and developed under Fred Duesenberg, raised output to 320 horsepower and was reputedly capable of 104 mph in second gear and top speeds of 130 mph. Thirty-six factory SJ cars were built, with a small number of additional long-wheelbase examples completed.
The bare chassis alone was priced at $8,500, with most completed cars falling between $13,000 and $19,000 (figures that placed the Model J in a category occupied by very few American automobiles of any period).
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