Whats the diff. between

Right you are MC.
The 1969 version of the 383 engine was upgraded to increase power output to 330 bhp (250 kW), and a new trim package called 'Cuda was released. The 'Cuda, based on the Formula S option, was available with either the 340, 383 and new for 1969 the 440 Super Commando V8.