Preheat the oven to 325° and butter and flour a 10-cup bundt pan. In a bowl, using a handheld electric mixer, beat the eggs with the sugar, vanilla extract, and orange zest at medium-high speed until smooth. Gradually beat in the orange olive oil until creamy, for about 2 minutes. In a small bowl, whisk the cake flour with the baking powder and salt. Add the dry ingredients to the egg mixture in 3 batches, beating on medium speed between additions.