With the initial success of the Gran Sport, Buick added several variants when the 1968 redesign occurred. Now available as the California Gran Sport, Gran Sport 350, Gran Sport 400, and eventually the Gran Sport 455, Buick had a GS for everyone. The top of the line GSX offered more torque and standard equipment than any other muscle car of the era.

Creates a considerably hotter spark that lets the flame expand more rapidly in the combustion chamber and a more complete and efficient burn of the air/fuel mixture