Preheat over to 350 degrees. In a large bowl combine flour, 1 1/2 cups of sugar, baking soda and salt. In a small bowl whisk eggs, buttermilk and oil. Stir into dry ingredients just until moistened. Fold in raisins. Combine cinnamon and remaining sugar and set aside.
Spoon half of the batter into two greased 8X4 loaf pans. Sprinkle with half of the reserved cinnamon~sugar mixture. Spoon remaining batter into loaf pans and sprinkle the remaining sugar and cinnamon mixture on top. Cut through batter with a knife to swirl.
Bake 55 to 60 minutes or until a toothpick comes out clean. Cool in pans for 10 minutes before removing from pans to wire cooling racks. Makes 2 loaves.