The problem with Corvette that nobody talks about
The 1970 Buick GSX Stage 1 represents General Motors engineering at its most ambitious and Buick's marketing at its most uncharacteristic. The Stage 1 package took the 455 cubic inch engine and pushed it to 510 lb-ft of torque — more low-end torque than any other production car engine of the era.
Buick was not known for performance cars. The GSX was an attempt to compete in a market segment that Buick typically didn't occupy. It worked: the Stage 1 ran consistent 13-second quarter miles and was faster than many of its better-known competitors.
The values on GSX Stage 1 cars have risen but remain below equivalent Chevrolet and Pontiac performance models. This is the same brand-discount dynamic that affects the Oldsmobile 442. The cars are excellent. The badges aren't as celebrated.