It's not that the reduced compression went unnoticed. Dropping from 10.0:1 to 8.5:1 and detuning to run on regular fuels would affect anyone, Buick engineers included. The 455 saw a horsepower decline from 350 HP gross to 315, and even the mighty Stage 1 fell from 360 to 345. Transmission choices remained the same, but axle ratios did not- the 3.61: 1 was dropped from the options list.
While the GS was still a very powerful car, the results were inescapable- The GS 455 was about a second slower ET in the quarter mile. Times were changing already, and soon an oil embargo would replace "What'll she do?" with "What'll she get?" as fuel economy becomes a prime target for engineers.
But for a couple more years, the Gentleman's Hot Rod, as the GS has become known, will stick around, although sales numbers would trend downward. Only 9,170 Gran Sports left the factory in total for the strike-shortened 1971 model year, which broke down as follows:
GS 350 Coupe- 5,986
GS 455 Coupe- 1,481
GS 455 Stage 1 Coupe- 801
GS 350 Convertible- 656
GS 455 Convertible- 165
GS 455 Stage 1 Convertible - 81
Oh, and of those 81 Stage 1 convertibles, only 9 had a manual transmission. And a total of 124 GSX were produced in 1971. Note that it was a trim option and is already included in the count of 9,180.
It's easy to see that the 1971 Buick GS was rare even when new and very highly prized indeed today.
Please enjoy our gallery of the GS 350 and GS 455 of 1971: