headers vs manifolds on a 318 2bbl difference ????

The problem with engines with Dyno numbers and the car not operating to the Dyno numbers are not the Dyno nor the car it is operator of said engine or car not optimizing the rest of the package to run what it's supposed to. If I choose to put a 3500 rpm converter behind my engine that makes peak torque at 5000 rpm it would be a slow turd but it would still have that peak torque.