Buick Skylark GS 400
The Buick Skylark GS (Gran Sport) was the gentleman's muscle car. While Pontiac had the GTO and Chevrolet the Chevelle SS, Buick's entry offered something different — turbine-smooth power delivery from the torque-rich 400 Buick V8, combined with better interior appointments and a more refined driving experience. The GS 400 packed 340 horsepower and a massive 440 lb-ft of torque in its most potent form. Buick engines were known for their smoothness and low-end grunt, making the GS a devastating traffic light-to-traffic light performer. The Stage 1 option pushed output to 360 hp with a special cam, larger valves, and revised carburetor. GS 400s and GS 455 Stage 1 cars are increasingly recognized as undervalued muscle cars.
GS cars are undervalued compared to GTO and Chevelle SS equivalents — making them potential bargains. Stage 1 cars command significant premiums. The Buick 400/455 is a torque monster but shares few parts with other GM engines. Check for correct GS trim and engine codes. A-body rust is the main enemy.
The GS designation replaced the Skylark Gran Sport in 1968. The GS 400 was replaced by the GS 455 for 1970. Stage 1 was the top performance option. Total production was always lower than GTO or Chevelle SS, making GS cars rarer.