G.M. thought that would work, too, with the V-8-6-4. It was supposed to start out on 8 cylinders and end up running on 4 when you got to a certain speed. It was a disaster.
Well, you know the new 5.7 Hemi's (at least the truck ones, not sure about the car version) do that, and it seems to work quite well, and does save gas. Of course, the engine was designed for it to work, not the same thing as just unplugging half the plug wires!
