In Victoria a Certificate of Roadworthiness is generally required when a car is sold or if a used car is to be re-registered. 

A Certificate of Roadworthiness can only be issued by a licensed car tester, operating from a nominated garage or service station.

The inspection is a check of the car to ensure that key components have not worn or deteriorated and that the car is safe for normal road use.

High Powered Cars

Probationary driver licence holders cannot driving high powered motor cars.  Driving a high powered motor car attracts a heavy fine and may result in licence suspension.

Restrictions may vary between states. 

Queensland Transport
RTA NSW
VicRoads

Car Modifications

A person cannot modify a car which is intended for use on a road, except with the approval of or in accordance with statutory guidelines. Restrictions may vary between states.

Department for Transport Energy and Infrastructure, South Australia
Department of Planning and Infrastructure, Western Australia
Queensland Transport
RTA NSW
VicRoads