Whisk together flour, baking soda, salt, cinnamon, and baking powder.
In a large bowl, beat the eggs. Gradually beat in sugar, then oil. Add flour mixture alternately with zucchini into the egg mixture. Stir in the raisins, walnuts, and vanilla. Pour batter into two 9 x 5 inch greased and lightly floured loaf pans.
Bake on lowest rack of the oven at 350 degrees F (175 degrees C) for 55 minutes. Let cool for 10 minutes in the pan, then turn out onto racks to cool completely. To freeze, wrap loaves in plastic wrap, and then wrap in heavy freezer paper. Will keep indefinitely.