Combine 3/4 cup white sugar, flour, salt, crushed pineapple, sour cream, and lemon juice in a saucepan. Cook over medium heat, stirring frequently, until the mixture is thick and bubbly. Gradually pour the cooked pineapple mixture into the beaten egg yolks, whisking constantly; return mixture to the saucepan. Continue to cook, stirring constantly, for 2 to 3 minutes longer. Remove from heat and let cool.
Beat egg whites, vanilla and cream of tartar until soft peaks form. Gradually stir in the remaining 1/3 cup sugar and continue to beat egg whites until stiff and glossy.
Spoon cooled filling into graham wafer crust and top with the meringue. Bake in preheated oven for 12 minutes or until golden. Let pie cool and serve.