Chaz Mostert has completed a successful shakedown of his new Walkinshaw Andretti United chassis.
Mostert will return for a second season with WAU, having joined the Holden team last year.
WAU has built a new chassis for the 2014 Bathurst winner, who finished fifth overall last season.
At Phillip Island on Wednesday, Mostert completed approximately 60km of running in the #25 Mobil 1 Appliances Online Racing WAU Commodore.
The 28-year-old will be joined for October's Repco Bathurst 1000 by Lee Holdsworth, who was confirmed with the team earlier this week.
Holdsworth was left without a full-time drive after Tickford Racing downscaled to three cars from 2021.
Several other teams took to Phillip Island for corporate ride days.
Mostert's former Tickford teammate, David Reynolds, competed his first laps aboard a Kelly Grove Racing Mustang.
Rick Kelly also substituted for the injured Andre Heimgartner, marking his first laps since he retired at the end of 2020.
The new Blanchard Racing Team operation also completed its first track day ahead of its 2021 debut.
WAU will take to Winton Motor Raceway for the official pre-season test on February 16.
The 2021 Repco Supercars Championship will commence at the Repco Mt Panorama 500 across February 26-28. Tickets are on sale now.