1953. 1955–1960 Completely new bodies and chassis were introduced for the 1955 model year and sales increased. A new overhead-valve Strato Streak V8 engine was introduced. With the introduction of this V8, the six-cylinder engines were discontinued; a six-cylinder would not return to the full-size Pontiac line until the GM corporate downsizing of 1977. In 1956, when Semon "Bunkie" Knudsen became general manager of Pontiac, alongside new heads of engineering, E. M. Estes and John DeLorean, Knudsen began reworking the brand's image. One of the first steps involved the removal of the "silver streaks" from the hood and deck lid which were a traditional styling feature beginning in 1933. These were eliminated from the 1957 models just weeks before they were introduced. The first Bonneville was also introduced. This was a version of the Star Chief convertible to showcase Pontiac's first fuel-injected engine. About 630 Bonnevilles were built in 1957. Pontiac marketing described it as "America's No. 1 Road Car". The following year, the Bonneville became its own line, built on the wheelbase of the A-body platform. A 1958 Tri power Bonneville was the pace car for that year's Indianapolis 500. The 1958 model year was final use of the "Indian" motif throughout the vehicle. The only exception would be the Indian head high-beam indicator light in the instrument cluster. All 1958 models featured ball joint front suspension replacing the previous kingpin design. With the 1959 model year, Pontiac came out with its "Arrowhead" emblem, with the star design in the middle. The "Arrowhead" design ran all the way up the hood from between the split grille, and on Star Chief models, had eight chrome stars from the emblem design on the body sides as chrome trim. Knudsen directed that the Pontiacs received a completely reworked chassis, body, and interior styling. Quad headlamps, as well as a longer, lower body, were some of the styling changes. The Chieftain line was renamed Catalina; the Star Chief was downgraded to replace the discontinued Super Chief series and for the first time did not have a two-door hardtop, only a two-door sedan along with a four-door hardtop and four-door sedan; in addition, there was no Star Chief wagon. The Bonneville was now the top of the line, coming in three body styles: a two-door hardtop, a four-door hardtop, and a four-door station wagon. The Star Chief's four-door "Vista" hardtop was also shared by