ZB Commodore

The Holden ZB Commodore was Holden's Supercars car from 2018 to 2022 — the Gen II-era liftback that replaced the VF Commodore and became the last Holden to race in the championship before the marque was retired and General Motors switched to the Chevrolet Camaro ZL1 for the Gen III era in 2023.

A silhouette of an import

The road-going ZB Commodore was a badge-engineered Opel Insignia B — a European front- and all-wheel-drive liftback, and the first Commodore not built in Australia after Holden closed its Elizabeth plant in 2017. None of that road-car layout suited a rear-drive V8 touring car, so the race ZB was a silhouette: the category's common control chassis and running gear clothed in a ZB-shaped, rear-drive body. Triple Eight Race Engineering, Holden's homologation team, developed the racing shape.

The Gen II control package

Under the Gen II regulations — which opened the category to two-door bodies and alternative engine configurations — the ZB kept the established formula. Beneath the panels it ran the common control chassis derived from the 2013 Car of the Future, a naturally aspirated 5.0-litre 90-degree V8 shared across the marques, a control rear-mounted six-speed sequential transaxle and control differential, the Dunlop control tyre and E85 control fuel. Mechanically it was the familiar Supercar; the ZB was a new body silhouette and aero package over that package rather than a new car underneath. Precise homologated dimensions and engine outputs are not published here as figures — they were managed to a control parity target.

Aero and the 2018 parity story

Blueprint/Gen aero is set by the technical rules rather than by free development, so the ZB's package (front bar, undertray, boot-mounted rear wing) is best described qualitatively. The car's 2018 debut aerodynamics were widely reported to be strong enough to prompt a mid-season aero parity review by the category — one of the recurring parity episodes of the Gen II era. The detail of any adjustment is not sourced here and is treated qualitatively.

Brakes, wheels and tyres

The tyre was the single-make Dunlop control. Brakes and wheels, by contrast, were not standardised in Gen II — supplier and specification varied by team, with several approved brake makes in use across the field; the single control-brake package only arrived with Gen III in 2023. Any single brake or wheel make quoted for the ZB reflects one team's fitment, not a category standard.

Evolution

The ZB raced through 2022 as the last car to carry the Holden badge. Holden as a marque was wound down by GM from 2020, but the ZB continued under the badge until the Gen III Camaro ZL1 took over General Motors' entry for 2023.

Sources: Gen II era control-formula catalogue rows (5.0L V8, control transaxle/differential, E85, Dunlop, Car-of-the-Future-derived control chassis) + the prior article — Grade D. No period official Gen II spec sheet or technical regulation was in hand; the 2018 aero-parity account is qualitative and unsourced here. Treat the technical rows as qualitative, control-target figures.