Set oven to 450 degrees Sift the flour and salt into a bowl. Beat the oil and water until thick and creamy; add to the flour. Mix with a fork until a ball of dough is formed. Roll out on a lightly floured surface to fit a 23 cm pie plate. Prick the bottom. Bake dozen minutes or until golden brown. Cool. Cream the butter, gradually adding the confectioners' sugar. Beat in the eggs until light and fluffy. Fold in the pineapple. Turn into a pie shell and chill until set. Decorated with whipped cream, if desired.