If by "coachbuilding" you mean putting bespoke bodies onto an existing chassis, it will never happen. First, no cars today have separate bodies and frames. The body of the car IS the frame. Second, cars from manufacturers have to meet crash requirements. You would have to crash test every variation of body you… » 9/19/14 12:29pm Friday 12:29pm

Yep. AMC designed the Pacer around the rotary, and was going to use GM's new rotary engine in the Pacer. You say GM never had a rotary engine? It's because at the 11th hour, GM pulled the plug on the project it leaving AMC with the automotive equivalent of blue balls. AMC had to scramble for another power source… » 9/10/14 12:06pm 9/10/14 12:06pm