Abstract: A modular intake manifold for an internal combustion engine that has a lower base member, a center runner section, and an upper shell. The lower base member has a series of outlets and witness marks formed within the outlets and attaches to an engine between right and left cylinder heads. The center runner section is situated within the base member for channeling incoming air into the series of outlets in the lower base member. The upper shell attaches to the lower base member, includes a throttle body mounting boss, seals and isolates the individual runner sections of the center runner section, and encloses the intake manifold. The intake manifold may be assembled and disassembled freely. Once disassembled, a different upper shell or center runner section, each having differing features from the components previously removed, may be reattached to the lower base member to alter the engine performance in some way.