The Buick GSX package was a special option for any 1971 or 72 Buick Skylark GS from the GS 350 the GS 455 stage I. If one wanted to order an  Buick GSX, your Buick dealer had to check off the special car order section of the form. Like other 1971 or 1972 Buicks the GSX additions used a deep tuned engine with 8.5:1 compression. But the Buick GSX with the stage one option was still one of the hottest muscle cars in town. Buick fans say it couldn't sit down the quarter mile faster than the LS 6 Chevelle. Both in 1971 Buick GSX in the 1972 Buick unit GSX is a special frame, a computer design rally tuned suspension and large diameter sway bars.