With an electric mixer, beat the sugar, eggs, and oil until smooth. Add the orange juice and mix well. Sift together the flour, salt, baking soda, and cinnamon. Add the flour mixture to the sugar mixture and beat well. Add the vanilla. Stir in the walnuts and apples, until blended. Pour the batter into the pan. Bake for 1 hour and 30 minutes. Remove the cake from the oven, let it cool in the pan for 15 minutes, then turn out onto a cake plate.