3. Buick Century GS
After 1970, the muscle car segment decline started. And in just a few short years, those glorious muscle cars disappeared from the scene. Buick tried their best to deliver great performance in luxury package. But after the slow sales of their 1971 and 1972 models, they decided to kill the GSX package.
However, in 1973, they renamed their Skylark line the Century. And that meant the engineers at Buick managed to sneak one more proper muscle car model, the Century GS. The Century GS was a Colonnade-style intermediate coupe. In fact, it was similar to those Pontiac and Oldsmobile intermediates with the characteristic front-end design. But the GS was just an appearance package that mimicked the looks of previous models.
The standard engine was the 150 HP 350 V8. However, if you optioned for the 455 Stage 1 big block, you could get 270 HP with revised brakes and suspensions. This version delivered some performance, so car fans consider it the last true Buick muscle car. However, the number of Century GS Stage 1 cars produced in 1973 is low. They only made around 700 of them with four-speed manual or three-speed automatic transmissions.