The brand-new 400ci V-8 for the GS400 was rated at 340 horsepower – still lower than some other brands, but on the street, the GS400 was competitive. Sitting on top of the 400 was what Buick ...

Still, Buick sold 19,257 GS cars in 1969, split almost equally between the 350-V8-powered examples (9,889) and the more muscular 400s (9,378).