The fun is under the huge bonnet mounted as a peculiar engine GMC V12 - called “702 Twin Six” (defined as you see the name of the model). 702 is the displacement in cubic inches, and in liters they have been a not inconsiderable 11.5 liters . It produces only 254 hp but its torque is much higher compared to other engines: 881 Nm at just 850 rpm. Although they do not report records on the stopwatch, it seems that the bullet designation is appropriate in this case.