The 1970 Buick GS represents the pinnacle of Buick performance
during the muscle car era. Since General Motors lifted the ban on
greater than 400cid engines in mid size models Buick was quick to
build a 455 cid version in the Gran Sport line.
The 455 cid engine featured bigger valves, hotter cam, more displacement,
and a functional cold air system that produced an absolutely stump
pulling 510 ft/lbs of torque. For the buyer looking for even more
power there was the Stage 1 option. Though Buick claimed the Stage
1 system was only good for 10 hp, quarter mile times for Stage 1
Buicks were nearly a half second better than the standard GS 455
cid. A Stage 1 engine featured special ported heads with larger
valves and revised valve springs, a hotter camshaft, and a tweaked
carburetor. These improvements along with a 3.64:1 geared positraction
made for nearly endless burnouts. With sticky tires a Stage 1 Buick
was capable of low 13 second quarter mile times.
The GSX was first offered in 1970 and was essentially a trim package
that included hood tachometer, Saturn Yellow or Apollo White paint,
low profile spoiler, unique black striping and blacked out hood
treatment, black bucket seats, floor shifter (Hurst for the four
speeds) disc brakes, wide oval tires, quick ratio steering and upgraded
suspension.
