One scene in the film shows an auto dealer billboard at his Buick Dealership saying "'73 model clearance, save $$$" I would say the person that commented it was a 1974 film that had scenes added would be correct. If you look at the cars in the film none are newer than 1974. Don't know how they came up with a 1983 release date unless it was released that year and was 10 years later than it was made. A great chase movie with real mayors and city folks in the movie. Don't think you could film that chase scene today with insurance and all. I used to live down in Torrance, CA and recognized the area and streets they used during the filming.