340's are rare. The best were the mid years of it's production 71 being the sought after original 340 Muscle Car's. By 1971 the 340's were refined. It replaced the 273 Commando in 1968. The 340 was phased out by 360's. I once had a 1970 340 Dart Swinger it had a 727 & drop out gears. The engine was pretty high compression with a big AVS Carter Four Barrel. Nice Plumb Crazy car with a white wrap around stripe and a very cool dash. The odd thing was it came with a bench seat and a auto on the tree, but it was the real deal. Someone said to me that it was experimental for the production of the 1971 Dodge Dart Sport. If you can find a 340 Six Pack car, it is worth as much as any other highly sought after Mopar. I have a 340 right now that I spent a fortune on, $5000 on just the bare long block.