Preheat oven to 350 degrees.
Butter and flour a 12-cup Bundt pan.
In a medium bowl, whisk together flour, lemon zest, baking soda, and salt; set aside.
Using an electric mixer, beat butter and granulated sugar on medium-high until light and fluffy, 4 to 5 minutes.
Add eggs one at a time, beating well after each addition.
Mix in lemon juice.
With mixer on low, alternately add flour mixture and sour cream, beginning and ending with flour mixture. Mix just until incorporated (do not overmix).
Spoon batter into prepared pan and smooth top with a rubber spatula. Firmly tap pan on a work surface to level batter.
Bake until a toothpick inserted in center of cake comes out clean; 55 to 60 minutes. If cake browns too quickly, tent loosely with aluminum foil.
Let cake cool in pan 30 minutes, then turn out onto a rack to cool completely.
(To store, wrap cake in plastic and keep at room temperature up to 3 days.)
Combine ingredients for Lemon Syrup in a small saucepan. Over medium heat, whisk the mixture until all the sugar has dissolved.
Poke holes all over the cooled cake, and brush with lemon syrup. If the cake does not absorb all the syrup at once, allow to sit about 20 minutes before continuing to brush with any remaining syrup.