1. Preheat oven to 350F.
2. In a large mixing bowl, combine flour, baking powder, cinnamon, nutmeg and salt.
3. In a separate mixing bowl beat together oil, sugar and eggs.
4. Add bananas and walnuts to egg mixture and blend thoroughly.
5. Add flour mixture and beat together to form a thick batter.
6. Turn out into a greased loaf pan and bake for 1 hour or until sharp knife inserted in center comes out clean. Cool on rack before removing from loaf pan.