The design principles that stand out the most to me on this Hot Rod Magazine cover from the 50s would be asymmetry, proximity, and framing. Asymmetry takes place due to the black rectangle and red rectangle across from each other causing a lack of symmetry. The car sitting on the lower half of the page creating a closer proximity to the black box then from the red title box. In this layout the boxes frame out the car making it center and the focus of the cover.
I found this image on Uppercase (journal blog) found here.