Lightly grease four small loaf pans and preheat the oven to 325 degrees. Sift flour with salt, baking powder, soda, and spices; set aside. In large bowl of an electric mixer on medium speed, beat sugar with butter just until blended.
Add eggs one at a time, beating well after very light and fluffy. Beat in pumpkin. At low speed beat in flour mixture until combined. Turn batter into greased pans, dividing evenly. Bake 1 hour, or until a cake tester comes out clean. Let cool in pans 10 minutes. Turn out onto wire racks to cool completely.