Ford claimed power outputs for the upgraded engines were around ten per cent higher than those of their XB predecessors.

[3] The increase was in part due to the fitting of much larger, stronger front and rear bumpers, and strengthening of the doors to comply with ADR29, which introduced strength and stiffness requirements for side-impact protection.

On sedan and wagon models, Ford also addressed the vision problems of the XA and XB by utilising redesigned rear doors, which debuted in May 1976 with the ZH series Fairlane,[5] with a lower window line that had the effect of removing the coke bottle styling of the XA and XB.

Visibility was further improved by an all-new, lower dashboard and crash pad,[3] and higher front seats.

These cars received XB GT-style blackouts and a sticker on the front doors consisting of Allan Moffat's signature and an Australian flag, as well as other options such as the GS Rally pack and Sports handling suspension as standard.

At the 1977 Hardie-Ferodo 1000, Allan Moffat and Colin Bond drove Group C specification Hardtops to a "1, 2" formation finish.

The GS 500 Hardtop formed the basis for the Ford Falcon Cobra and a customer racing program, with a special "Evolution" (and later Evo II) package to homologate parts.