the Chevette), the Sunburst (based on the Spectrum), the Firefly (based on the Sprint), the Tempest (based on the Corsica), the Sunrunner (based on the Tracker), the Pursuit (based on the Cobalt; later badged as the "G5 Pursuit" and simply "G5"), and the Wave (based on the Aveo; later badged the "G3 Wave" and "G3"). Engines Pontiac engineer Clayton Leach designed the stamped steel valvetrain rocker arm, a simplified and reliable alternative to a bearing-equipped rocker. This design was subsequently picked up by nearly every OHV engine manufacturer at one point or another. Pontiac began work on a V8 configuration in 1946. This was initially intended to be an L-head engine, and 8 experimental units were built and extensively tested by the end of the 1940s. But testing comparisons to the OHV Oldsmobile V8 revealed the L-head could not compete performance-wise. So, in addition to building a new Pontiac Engineering building in 1949–1951, the decision to re-direct the V8 to an OHV design delayed its introduction until the 1953 model year, however, the Buick division was introducing its new engine (Nail valve V-8) in 1953 and asked the corporation to hold back or delay Pontiac's V8 introduction until the 1955 model year which it did. In mid-1956, Pontiac introduced a higher-powered version of its V8. Among other things, this version of the engine was equipped with a high-performance racing camshaft and dual 4-barrel carburetors. This was the first in a series of NASCAR-ready pre- Super-Duty V8 engines and introduced the long line of multi-carburetor-equipped engines that saw Pontiac become a major player during the muscle car and pony car era of the 1960s. The enlarged 1956 Pontiac V8 found its way into light-duty GMC pickup trucks. Pontiac's second-generation V8 engines shared numerous similarities, allowing many parts to interchange from its advent in 1959 to its discontinuation in 1979. Displacement ranged from . The similarity of the engines (except for the 301 & 265 versions) makes rebuilding these engines relatively easier. This feature also made it possible for Pontiac to develop the modern muscle car, by the relatively simple process of placing its second largest-displacement engine, the into its mid-size car, the Le Mans, making the Pontiac LeMans GTO. From their inception in the 1950s until the early 1970s, Pontiac engines were known for their performance. The V8 was the largest and available in most Pontiacs except in the compact-size cars.