Of the 687 GSXs built, only 488 were ordered with the Stage 1 upgrade, so this car was pretty exclusive. The upgrade cost $113 on a GSX, but it was worth it. Motor Trend crowned it the "quickest American production car we have ever tested" after it ran a 13.38-second pass at 105.5 mph. Any way you cut it, Buick had earned its place on muscle's all-time, all-star team.