Buick GSX
Although the Buick brand was not associated with the performance there were more than a few Buicks that changed the game. The GSX was one of the high-performance models that made their way onto the market. With unique styling and one-of-a-kind paint jobs, the exterior styling of the GSX was excellent (via Hemmings).
But it was the performance of the GSX that set the car apart. The GSX was strictly designed to be a performance vehicle and there were only 678 produced. The fact that there was such a powerful Buick model was not unnoticed by the automotive world.