They came on 1976 Plymouth feather Duster and Dodge Dart Lite's only available in 76. Chrysler built these cars with a few aluminum parts like the trunk lid sub structure also the hood substructure and a few other minor parts. If I remember correctly the aluminum they used only sheaded around 180 or so pounds.....basically the weight of one adult. It was an effort to make the cars more efficient.....increase fuel milage. They used a lean burn slant six, with a specially tuned holley single barrel carb and an aluminum intake. I have heard that when these cars were equipped with the 833 OD trans they could achieve 30mpg.