A ram outlet header includes a ram outlet header body. A ram air fan mounting neck and a ram air fan mounting flange are configured to couple the ram outlet header to a ram air fan housing. A heat exchanger mounting flange is configured to couple the ram outlet header to a heat exchanger assembly. A lower face includes a first stiffener. A mid-section includes a second stiffener, a third stiffener, and a fourth stiffener. The ram air fan mounting flange is positioned between the lower face and the mid-section. A ratio of thickness of the second stiffener to the third stiffener is between 1.04 and 1.16, and a ratio of thickness of the fourth stiffener to the third stiffener is between 1.04 and 1.16.