The intake manifold is one of the major players in the combustion process that gives power to your Ford 300, whose power potential greatly depends on how quickly and efficiently the air/fuel mixture explodes in the combustion chamber, pushing the piston down the cylinder.
Ford 7.3 DIT Power Stroke Manual Online: exhaust manifolds, Measuring Exhaust Back Pressure Without Cold Weather Package. '98 Physical Id Exhaual Manilalds • The Driver Side ''F'' Series Exhausl Manifold Has Changed Co Allow The Use Of A Common Exhaust Up Pipe.