Preheat oven to 350 degrees F (175 degrees C). Grease and flour a 9×13 inch pan. In a medium bowl, stir together the sugar and apples, set aside. Sift together the flour, baking soda, cinnamon and salt.
In a large bowl, stir together the oil, eggs and vanilla. Add the apples and sugar, mix well. Stir in the dry ingredients, then the nuts. Pour into the prepared pan and spread evenly.
Bake in the preheated oven for 45 minutes, or until cake springs back to the touch.