Preheat oven to 315 F. Prepare a 16 cup bundt pan with homemade cake release, or with nonstick baking spray.

In a large mixing bowl, attached to a stand mixer fitted with a whisk attachment, beat the butter for 2 minutes on high until pale in color. Add in sugar and salt and cream together for an additional 5-7 minutes, scraping down the sides of the bowl a couple times. Mixture will be very pale yellow and fluffy.

Add in the eggs, one at a time, beating well after each addition.

Slowly add in flour, being careful not to over beat (turn the mixer down to low at this time). Pour in 7 Up and mix just until combined.

Pour batter into prepared pan and bake for 75-85 minutes, or until a toothpick inserted into the center comes out clean. Allow the cake to cool in pan for about 10 minutes, then invert on wire rack. Cool completely on a wire rack.