Brabham’s Cooper T23 Bristol was billed as the fastest car of its type in the world as a Jack’s ongoing development of it with Frank Ashby’s advice and mentoring off to the side.
These images from the Brabham Family Collection were taken at Mount Panorama during the Easter 1954 meeting, the start of the A-Grade scratch race.

Jack’s T23 being tended by Keith Holland in the white overalls and Arthur Gray of Belshaw Foundry in the blazer (Brabham Family)
I’ve done Cooper Bristols and Jack’s T23 chassis ‘CB/1/53’ to death, here; https://primotipo.com/2017/02/24/the-cooper-t23-its-bristolbmw-engine-and-spaceframe-chassis/ and here; https://primotipo.com/2016/06/24/jacks-altona-grand-prix-and-cooper-t23-bristol/
The other two photos are at Mount Druitt, Stephen Dalton reckons June 27 1954 or 8 August 1954, thanks to Stephen and John Medley for photo IDs.
Credits…
Brabham Family Collection, ‘The Jack Brabham Story’ Jack Brabham with Doug Nye, Stephen Dalton, John Medley
Tailpiece…
Finito…