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Why do that when Germany could mass produce the superior Ju-252?
I don't believe that.
The German economy was out muscled by the economies of Britain, the Soviet Union and the USA. Germany had to make tough choices as to what weapons would provide the most bang for the buck. German leadership decided Ju-252s weren't worth the price so the aircraft wasn't placed into mass production. They could have produced Ju-252s while cutting something else such as the V2 rocket program.
The engines of the Ju 52 and the SM.82 were not in the same class - Ju 52 had about 700PS engines, SM.82 950PS engines