At mid-year 1977, Pontiac introduced the Phoenix, an upscale version of the Ventura which replaced the Ventura entirely after the end of the 1977 model year. Pontiac also introduced its 151 cubic inch "Iron Duke" 4-cylinder overhead valve engine. It was first used in the 1977 Astre, replacing Astre's aluminum-block 140 cubic inch Vega engine. The 'Iron Duke' engine would later go into many GM and non-GM automobiles into the early 1990s. The 151 cubic inch L4 and the 301 cubic inch V8 were the last two engines designed solely by Pontiac. Subsequent engine design would be accomplished by one central office with all designs being shared by each brand.