The 340 started out in Darts and Barracudas in like 1968. The Duster isn't the legend , it was just a way for Plymouth to keep marketing the 340 after the 'Cuda went E body. The demon is a Dart, which had the 340 first. The 340 engine is the "Legend" in all reality. Goood pot stir by the way ;)
Well technically yes but I've heard a lot of "Duster 340" stories over the last few years. And the story of how they came about it's still far more legendary than the "rebranded Duster" aka Demon. ;) lol
