Ingredients4 cups uncooked elbow macaroni1 cup mayonnaise1/4 cup distilled white vinegarTwo thirds of a cup of white sugarTwo and half tablespoons prepared yellow mustardOne and half teaspoon of saltHalf of a teaspoon ground black pepper1 large onion, chopped2 stalks celery, chopped1 green bell pepper, seeded and choppedDirectionsBoil a large pot of lightly salted water.  Add the macaroni and cook until its tender for about 8 minutes. Drain the water from the macaroni after boiling. Mix the mayonnaise, vinegar, sugar, mustard, salt and pepper in a large bowl. Stir in the onion, celery, green pepper, carrot, pimentos and macaroni in the same large bowl containing the mixture of mayonnaise. Refrigerate for at least 4 hours before serving.