Today, dollar for dollar, is the 318 faster than the 340 ???

It is known that Chrysler under rated those numbers. Mopar Manipulatin - Hotrod Magazine Aug/Sep '69 (I believe?) dispells that rating.

They did not do that JUST to the "Glory 340".

A 2.2 Shelby rated at 110 HP was dynoed at 118 dead stock. Then the Air Pump belt was cut and now it was 124HP, changed the Champions out to some Autolite Copper Truck plugs 2 steps colder and got 126, three aircleaner gaskets netted another 1 HP and final was a real good tune on the computer and it was at 129.6 HP.
While not KILLER it is still under rated from the factory.