Preheat oven to 350°F. In a large bowl stir together the eggs, granulated sugar, melted margarine, and vanilla. Stir in the cooked sweet potatoes and raisins. Spread the mixture evenly in an ungreased 2-quart square baking dish.
For topping, in a small bowl, combine brown sugar and flour. Cut in margarine until mixture resembles coarse crumbs. Stir in pecans. Sprinkle over sweet potato mixture. Bake in preheated oven for 20 minutes or until heated through. Makes 8 servings.