Beat the eggs until light and foamy. Gradually add oil and sugar, mixing well. Add zucchini and vanilla. Mix lightly, but well. Sift together flour, soda, baking powder, salt and cinnamon. Add to creamed mixture. Mix just until moistened. Stir in pecans. Pour into 2 greased and floured 9 x 5 inch loaf pans. Bake at 325ºF. for 1 hour or until well done.