Owner of VIP Petfoods, which calls itself Australia's premier producer of fresh chilled pet foods, Mr Quinn declined to divulge his investment contribution, but said he hoped to be able to repay local, community support by building a quality facility.
"I'm prepared to put in enough to make it something that the region and everyone will be proud of," he said.
The general manager of Cromwell Motorsport Park Trust Ltd, David McKewen, said it was a stroke of "good fortune" someone with Mr Quinn's enthusiasm for the project, and commitment to invest, had come on board.
Mr McKewen said the park was "still a significant development", and would cost about $20 million.
The trust has a resource consent to develop a motorsport park on land beside the Cromwell speedway.
The consent covers provision for vehicle testing, driver schools and training, tourism activities, corporate activities including promotions, the film industry, and motorsport.
The development also has provision for an automotive-related commercial park.
Current shareholders Allan Dippie, Ian Begg (both of Dunedin), Grant Aitken (Queenstown) and Scott O'Donnell (Invercargill) would drop their director status but remain shareholders, and Mr Quinn would become sole director, Mr McKewen said.
A passionate motorsport competitor and sponsor, Mr Quinn said he had industry contacts who would help him to pursue a particular dream for the park.
"One of the main things I want to establish there is a motorsport museum." This would include New Zealand "legends of motorsport", and cars.
Track plans were being finalised, and the trust hoped to have some facilities open early next year, Mr McKewen said.
Mr Quinn (55) and wife Christina came in at 38th on Queensland's Top 100 Rich List 2011, with a worth of $A265 million ($NZ342.2 million).
Mr Quinn came from humble beginnings. An accompanying profile story from the 2010 list says he grew up in a "home-made caravan in Scotland".
Mr Quinn described himself as having been "very successful in pet food", and fortunate enough to be able to promote his company's brand by sponsorship and racing.
"I'm really a pet-food maker that discovered when I was 18 years old that I was not going to make a fortune as a racing driver," he said, with a laugh.
He owns a property in the lower Shotover area, near Queenstown, and is looking forward to spending more time in Central Otago.
Mr Quinn is no stranger to New Zealand's roads, having won the Targa New Zealand tarmac rally for the past three years.
His company has sponsored, among others, teams in the Australian V8 Supercars.
