Actually the EMB-145 first version (Versao 1) had stretched fuselage too. Since Embraer wanted to use the Brasilia wing, the jet pods configuration was modeled on the Brasilia's turboprop nacelles. Embraer contracted out to Boeing extensive wind-tunnel and computational fluid dynamics studies, results of which was negative, essentially due the sweep angle and profile of the wing. Boeing suggested a pylon-nacelle configuration of the engines and a new, more swept wing, and lenghten more the fuselage to house 50 passengers. . And this was Versao 2. In the end, the final configuration was a compromise, using the more swept wing and lenghtened fuselage but putting the engine on the rear to ease the design job for the supercritical wing.