Austin 7 racer boy Peter Brock found at the factory

The car, originally modified by 12-year-old Brock with an axe, was the vehicle that Brock learned to drive on the family farm in Victoria.

"It's really amazing," Brock's brother Lewis said yesterday.

“Peter rode it all over the farm and I sat in the back holding the battery most of the time.

“He picked up a motorsport bug in that car.

“Here he learned his early racing trade.

"This thing had no brakes, so Peter had to throw a huge slide to stop it."

Brock died in September in a car accident in Western Australia, and a nationwide search for all of his cars failed to find the original.

The modified car is believed to have been sold by Brock's father, Jeff, along with other junk while cleaning the farm.

The chassis was found "stored" on the roof of a plant in Victoria last month and was identified by young Brock's ax marks.

The vehicle was purchased from a factory owner and will be donated to the Peter Brock Foundation.

The chassis will be fully restored to original condition with the help of the Austin 7 Club in order to compete in future historic races.

The car was originally bought by Brock's father as a road car and later modified with an axe.

Father and son then welded a steel frame to the chassis and installed a seat to make Brock's first race car.

"It's a miracle he survived," Lewis Brock said.

“It was a bit like karting in the 1950s.

“It helped him realize that he had such an affinity for cars, racing and driving. It was a paramount decision for him to make a career in racing.

“This is the first car Peter built and the first car he drove. It's very important to his story."