1970 318 duster exhaust question???

Alpha13.. I'm sure you are right with your explanation in regards to the pipe size argument. But In my ignorance, it just goes against my limited concept of how this stuff works! I always heard that, to make more power, let the engine "breathe" better. Usually this is done in the first stages with a better intake and exhaust manifolds / headers.

The way an engine works has been likened to the way an air compressor works. To get the most efficient air production, the air hose itself (exhaust pipe) needs to be of adequate size, otherwise performance drops off significantly.

Don't get me wrong, I'm not saying that you're incorrect. I'm just trying to wrap my brain around the idea of the smaller pipe being a better option. I'm getting ready to put dual exhaust (2 1/2") on my Dart... Hoping for an improved performance factor!