1970 Buick GSX Stage 1
Available exclusively in Saturn Yellow or Apollo White, the 1970 GSX was Buick’s answer to the GTO Judge and Oldsmobile’s 442, and by most measures, the most formidable of the three.
Front and rear spoilers, bold tape graphics, a hood-mounted tachometer, and wide G60-15 Goodyears on chrome five-spoke wheels gave the GSX an appearance that left little ambiguity about its intentions.
The standard GSX carried a 455 CI big-block rated at 350 hp (gross), but the optional Stage 1 package took things considerably further. Larger valves with stronger springs, a higher-lift camshaft, revised carburetor calibration, and a less restrictive exhaust brought the official output to 360 hp (gross), a figure Buick deliberately kept conservative.
Period dyno testing and road results suggested the true output was significantly higher, and Motor Trend recorded a 13.38-second quarter-mile at 105.5 mph in a Stage 1 test car. The torque figure of 510 lb-ft at just 2,800 rpm was extraordinary for any car of the period.
Total GSX production for 1970 ran to 678 units, with 400 factory-built Stage 1 cars documented for the model year. Four-speed cars accounted for 199 of the Stage 1 total, making manual-transmission examples among the scarcest survivors of an already short production run.
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