Lot #1230 - Only 124 total GS 455s were produced with the GSX option package. For 1971, Buick added the brand new 455cid engine into its restyled GS. The 455 had more displacement, bigger valves, a hotter cam and included standard cold air induction through functional hood scoops. Torque was rated at a tire shredding 510ft/lbs. The Stage 1 package upped the ante with an even hotter cam, bigger valves in special high-compression heads, distributor with more timing and a modified Rochester carburetor. Buick rated it at 360hp, but most testers believed it was more than 400hp. Gran Sport appearance details included a custom painted hood, accent striping, blacked out grille, rear spoiler, dual hood air scoops and GSX monograms. Heavy-duty suspension disc brakes, 3.42 rear end and a Hurst shifter rounded out the package. From the Michael Jenkins Collection. Factory option poster. GSX license plate. Notebook of documentation.