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A new application for the use of aluminum powder metallurgy in automotive engines has been developed. The dual overhead cam Northstar engine which began production in the 1993 model year uses aluminum metal powder for the camshaft bearing caps in the cylinder head assembly. The material was chosen because it offered the opportunity to eliminate both the machining operations and the capital required for the machines when compared to traditional die cast bearing caps. Tolerances for the P/M cap were essentially the same as those for traditional machining operations, and from a functional perspective, they performed equally as well as the die cast parts. Cam bearing caps for overhead cam engines are typically made as high pressure aluminum die castings which are subsequently machined to provide flat mating surfaces, bolt holes, and many other features.

General Motors Powertrain Division has developed a new V-8 engine for Cadillac vehicles in the 1990s. The Northstar engine incorporates the use of aluminum for both the cylinder block and head and other lightweight materials throughout. The valve train incorporates direct acting hydraulic lifters actuating the four valves per cylinder through dual overhead camshafts. The primary focus of the project has been to produce an engine of unquestioned reliability and exceptional value which is pleasing to the customer throughout the range of loads and speeds. The engine was designed with a light weight valve train, low valve overlap and moderate lift, resulting in a very pleasing combination of smooth idle and a broad range of power. The use of analytical methods early in the design stage enabled systems to be engineered to optimize reliability, pleaseability and value by reducing frictional losses, noise, and potential leak paths, while increasing efficiency and ease of manufacture.