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Eric Minoff on the La Grande Dual Cowl Phaeton

The Model SJ, the supercharged version of the J, debuted in 1932 originally equipped with a set of eight separate hard pipes, the arrangement you see on this car. The early hard pipes, as they were referred to, only existed for less than a year, at which point they replaced with the 4 flexible stainless steel pipes you see on virtually all SJ and many J's.

The stainless pipes were so racy and popular at the time (Mercedes-Benz, Maybach, Rolls Royce, Bentley, Delahaye, Delage, Talbot-Lago, Auburn, and many others all had them), that many owners actually converted their hard pipe SJ's (or no external pipe J's) to the 4 stainless steel pipes. While these pipes did have their advantages, such as prestige and (on SJ's) the ability to disconnect the pipes for a [loud] boost of power, some owners liked their hard pipe SJ's too much to change them.

One owner went so far to tell August Duesenberg (after the owner had received a notice from the company offering to change the pipes) that he loved his hard pipes b/c they glowed at night and impress my girlfriend! Hence, you can definitely tell if a Duesenberg is an SJ if it has hard pipes, but cannot if it has stainless steel ones.