Car: Buick Century Gran Sport Stage 1
What makes it special: For 1973, Buick renamed its intermediate line from Skylark to Century, receiving new Colonnade styling, which was basically a pillared hardtop sedan. The GS became the "Gran Sport" and was now an option package on the semi-fastback Century 350 Colonnade coupes. The option included decals on the rear fenders and trunk lid reading "gran sport" along with suspension and appearance upgrades.
What made it famous: Two 455 cu in V8's were available including the 250 hp 4-barrel and the 270 hp Stage 1 4-barrel, both with dual exhaust. More than 700 1973 Century GS models were built with the Stage 1 455, with most of them equipped with the 3-speed Turbo Hydra-matic 400, and a small number with the 4-speed manual transmission.
Why I would want one: I've always liked the styling of the 1973 Buick Century, and have long admired the Buick Stage 1 offerings, so the mating of these two would be a no-brainer as to wanting to have one of my own.
Fun fact: The name Gran Sport replaced the GS moniker with the 1973 Gran Sport, and was again revived in the late eighties on the FWD Skylark model with various performance options added.
( 1973 Buick GS Stage 1 photo from hooniverse.com )