Preheat oven to 400*F.
Combine sugar, 1/3 cup flour, eggs, sour cream, and vanilla in a large bowl; stir until smooth. Gently fold in red raspberries then spoon into unbaked pie shell.
Bake for 30 to 35 minutes, or until the center is set. Remove from oven.
Combine 1/2 cup flour, brown sugar, chopped pecans, and softened butter; sprinkle over the hot pie. Continue baking at 400*F for 10 minutes, or until golden brown.