The HZ series was launched in October 1977 and was the final revision of the Holden HQ seroes.
The introduction of Radial Tuned Suspension and 4 wheel disc brakes was a dramatic improvement, which brought remarkable advances in ride, handling and improved safety.
Holden had mastered Australian conditions better than any other on the road before.
The HZ was also the last of the traditional sized Holdens, until the smaller, lighter Commodore replaced it the following year in 1978.