All turbo charged engines use some oil, depending on their condition and the owners driving style. Your dad's saf will use some but probably so little that its barely noticeable. Unfortunately, Your car sounds in pretty poor shape. Ford manuals used to quote that the cosworth engine could consume up to 1 litre of oil every 6oo miles but i've yet to see a road going one that ever used that much day to day....... Either you have a very nasty leak somewhere, or the internals are worn and in need of a rebuild