Combine 2 cups sugar, oil, and eggs in a large bowl, beating with a whisk until blended. Stir in the apple, 1 cup pecans, and vanilla.
Combine the flour, soda, salt, 1 teaspoon cinnamon, and nutmeg; add to the apple mixture, stirring until blended (batter will be thick). Spread the batter into a greased and floured 13 x 9 x 2 inch pan.
Combine the remaining 1/3 cup sugar, 1/2 cup pecans, and 1 tsp cinnamon; sprinkle evenly over the batter.
Bake at 350 degrees for 45 to 50 minutes or until a wooden pick inserted in the center of the cake comes out clean. Cool in the pan on a wire rack. Cut into squares and serve.